Androstanolone, or stanolone, also known as dihydrotestosterone (DHT) and sold under the brand name Andractim among others, is an

androgen An androgen (from Greek ''andr-'', the stem of the word meaning "man") is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This inc ...

and

anabolic steroid Anabolic steroids, also known more properly as anabolic–androgenic steroids (AAS), are steroidal androgens that include natural androgens like testosterone (medication), testosterone as well as synthetic androgens that are structurally related ...

(AAS) medication and

hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...

which is used mainly in the treatment of low testosterone levels in men. It is also used to treat

breast development Breast development, also known as mammogenesis, is a complex biological process in primates that takes place throughout a female's life. It occurs across several phases, including prenatal development, puberty, and pregnancy. At menopause, br ...

and small penis in males. It is typically given as a

gel A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state, although the liquid phase may still dif ...

for application to the skin, but can also be used as an

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ar ...

by injection into muscle.

Side effect In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequence ...

s of androstanolone include

symptom Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showin ...

s of

masculinization Virilization or masculinization is the biological development of adult male characteristics in young males or females. Most of the changes of virilization are produced by androgens. Virilization is most commonly used in three medical and biology ...

acne Acne, also known as ''acne vulgaris'', is a long-term Cutaneous condition, skin condition that occurs when Keratinocyte, dead skin cells and Sebum, oil from the skin clog hair follicles. Typical features of the condition include comedo, black ...

, increased hair growth,

voice changes ' A voice change or voice mutation, sometimes referred to as a voice break or voice crack, commonly refers to the deepening of the voice of men as they reach puberty. Before puberty, both sexes have roughly similar vocal pitch, but during puberty ...

, and increased

sexual desire Sexual desire is an emotion and motivational state characterized by an interest in sexual objects or activities, or by a drive to seek out sexual objects or to engage in sexual activities. It is an aspect of sexuality, which varies significantly ...

. The medication is a

naturally occurring A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical sy ...

androgen and anabolic steroid and hence is an

agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...

of the

androgen receptor The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone in th ...

(AR), the

biological target A biological target is anything within a living organism to which some other entity (like an endogenous ligand or a drug) is directed and/or binds, resulting in a change in its behavior or function. Examples of common classes of biological targets ...

of androgens like

testosterone Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testes and prostate, as well as promoting secondar ...

and DHT. It has strong

ic effects and weak muscle-building effects, as well as no

estrogen Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal acti ...

ic effects. Androstanolone was discovered in 1935 and was introduced for medical use in 1953. It is used mostly in

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

and

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to th ...

. The drug has been used by weightlifters to increase performance due to its powerful androgenic properties. The medication is a

controlled substance A controlled substance is generally a drug or chemical whose manufacture, possession and use is regulated by a government, such as illicitly used drugs or prescription medications that are designated by law. Some treaties, notably the Single C ...

in many countries and so non-medical use is generally illicit.

Medical uses

Androstanolone is available in

pharmaceutical A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...

formulation Formulation is a term used in various senses in various applications, both the material and the abstract or formal. Its fundamental meaning is the putting together of components in appropriate relationships or structures, according to a formul ...

s for medical use as an androgen. It is used mainly as a form of

androgen replacement therapy Androgen replacement therapy (ART), often referred to as testosterone replacement therapy (TRT) or hormone replacement therapy (HRT), is a form of hormone therapy in which androgens, often testosterone, are supplemented or replaced exogenously ...

in the treatment of male

hypogonadism Hypogonadism means diminished functional activity of the gonads—the testes or the ovaries—that may result in diminished production of sex hormones. Low androgen (e.g., testosterone) levels are referred to as hypoandrogenism and low estrogen ...

and is specifically approved for this indication in certain countries. However, it is no longer recommended for this purpose due to biological differences from testosterone such as lack of estrogenic effects and partial androgenic effects.

Topical A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...

androstanolone is useful in the treatment of

gynecomastia Gynecomastia (also spelled gynaecomastia) is the abnormal non-cancerous enlargement of one or both breasts in males due to the growth of breast tissue as a result of a hormone imbalance between estrogens and androgens. Updated by Brent Wisse (1 ...

. Similarly, androstanolone enanthate via

intramuscular injection Intramuscular injection, often abbreviated IM, is the injection of a substance into a muscle. In medicine, it is one of several methods for parenteral administration of medications. Intramuscular injection may be preferred because muscles have ...

has been found to be effective in the treatment persistent

pubertal Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a girl, the testes in a boy. ...

. The medication has also been used as a topical gel to treat small penis in pre- and peripubertal boys with mild or

partial androgen insensitivity syndrome Partial androgen insensitivity syndrome (PAIS) is a condition that results in the partial inability of the Eukaryote#Animal cell, cell to respond to androgens. It is an X linked recessive condition. The partial unresponsiveness of the cell to the ...

. Androstanolone was found to be effective in the treatment of advanced

breast cancer Breast cancer is cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or a re ...

in women in the 1950s, although it was used in very high doses and caused severe

virilization Virilization or masculinization is the biological development of adult male characteristics in young males or females. Most of the changes of virilization are produced by androgens. Virilization is most commonly used in three medical and biology ...

. It was used as a

microcrystalline A microcrystalline material is a crystallized substance or rock that contains small crystals visible only through microscopic examination. There is little agreement on the range of crystal sizes that should be regarded as microcrystalline, but th ...

aqueous suspension In chemistry, a suspension is a Mixture#Homogeneous and heterogeneous mixtures, heterogeneous mixture of a fluid that contains solid particles sufficiently large for sedimentation. The particles may be macroscopic, visible to the naked eye, usual ...

. Shortly thereafter,

drostanolone propionate Drostanolone propionate, or dromostanolone propionate, sold under the brand names Drolban, Masteril, and Masteron among others, is an androgen and anabolic steroid (AAS) medication which was used to treat breast cancer in women but is now no long ...

(2α-methylandrostanolone propionate) was developed for this use instead of androstanolone due to its superior

pharmacokinetics Pharmacokinetics (from Ancient Greek ''pharmakon'' "drug" and ''kinetikos'' "moving, putting in motion"; see chemical kinetics), sometimes abbreviated as PK, is a branch of pharmacology dedicated to determining the fate of substances administered ...

and was introduced for this indication in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

and

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

in the early 1960s. Androstanolone was used at a dose of 25 mg sublingually two to three times per day in androgen replacement therapy for men. This is also the

anabolic Anabolism () is the set of metabolic pathways that construct molecules from smaller units. These reactions require energy, known also as an endergonic process. Anabolism is the building-up aspect of metabolism, whereas catabolism is the breaking-do ...

dosage of androstanolone in men.

Available forms

Androstanolone is available as a 2.5% hydroalcoholic

given transdermally in doses of 5 or 10 g/day (brand name Andractim). The medication was previously available as a 10 mg

oral The word oral may refer to: Relating to the mouth * Relating to the mouth, the first portion of the alimentary canal that primarily receives food and liquid **Oral administration of medicines ** Oral examination (also known as an oral exam or or ...

tablet with 300 mg L-lysine (brand name Lysinex) and as a 25 mg

sublingual Sublingual (abbreviated SL), from the Latin for "under the tongue", refers to the pharmacological route of administration by which substances diffuse into the blood through tissues under the tongue. The sublingual glands receive their prima ...

tablet (brand names Anabolex, Anaprotin, Anabolene, Anaboleen, Proteina). The medication has also been marketed in the form of several androstanolone esters, including androstanolone benzoate (brand names Ermalone-Amp, Hermalone, Sarcosan), androstanolone enanthate (brand name Anaboleen Depot),

androstanolone propionate Androstanolone propionate (brand name Pesomax), also known as stanolone propionate or dihydrotestosterone propionate (DHTP), as well as 5α-androstan-17β-ol-3-one 17β-propionate, is a synthetic androgen and anabolic steroid and a dihydrotestost ...

(brand name Pesomax), and

androstanolone valerate Androstanolone valerate (brand name Apeton), also known as stanolone valerate or dihydrotestosterone pentanoate, as well as 5α-androstan-17β-3-one 17β-valerate, is a synthetic androgen and anabolic steroid and a dihydrotestosterone ester. It i ...

(brand name Apeton), which are provided as

oil solution An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...

s for

at regular intervals.

Side effects

Adverse effect An adverse effect is an undesired harmful effect resulting from a medication or other intervention, such as surgery. An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect. The term complica ...

s of androstanolone are similar to those of other AAS and include

ic side effects like

oily skin The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue guarding muscles, bones, ligaments and internal organs. Human skin is similar to mos ...

seborrhea A sebaceous gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in the greatest numbe ...

, increased

facial A facial is a family of skin care treatments for the face, including steam, exfoliation (physical and chemical), extraction, creams, lotions, facial masks, peels, and massage. They are normally performed in beauty salons, but are also a com ...

body hair Body hair, or androgenic hair, is the terminal hair that develops on the human body during and after puberty. It is differentiated from the head hair and less visible vellus hair, which is much finer and lighter in color. The growth of androge ...

growth Growth may refer to: Biology * Auxology, the study of all aspects of human physical growth * Bacterial growth * Cell growth * Growth hormone, a peptide hormone that stimulates growth * Human development (biology) * Plant growth * Secondary growth ...

scalp hair loss Pattern hair loss (also known as androgenetic alopecia (AGA)) is a hair loss condition that primarily affects the top and front of the scalp. In male-pattern hair loss (MPHL), the hair loss typically presents itself as either a receding front ha ...

, and increased

aggressiveness Aggression is overt or covert, often harmful, social interaction with the intention of inflicting damage or other harm upon another individual; although it can be channeled into creative and practical outlets for some. It may occur either reacti ...

and

sex drive Libido (; colloquial: sex drive) is a person's overall sexual drive or desire for sexual activity. Libido is influenced by biological, psychological, and social factors. Biologically, the sex hormones and associated neurotransmitters that act up ...

. In women, androstanolone can cause partially irreversible

, for instance

voice deepening A hoarse voice, also known as dysphonia or hoarseness, is when the voice involuntarily sounds breathy, raspy, or strained, or is softer in volume or lower in pitch. A hoarse voice, can be associated with a feeling of unease or scratchiness in the ...

hirsutism Hirsutism is excessive body hair on parts of the body where hair is normally absent or minimal. The word is from early 17th century: from Latin ''hirsutus'' meaning "hairy". It usually refers to a "male" pattern of hair growth in a female that ...

clitoromegaly Clitoromegaly (or macroclitoris) is an abnormal enlargement of the clitoris that is mostly congenital or acquired, though deliberately induced clitoris enlargement as a form of genital body modification is achieved through various uses of anabo ...

breast atrophy Breast atrophy is the normal or spontaneous atrophy or shrinkage of the breasts. Breast atrophy commonly occurs in women during menopause when estrogen levels decrease. It can also be caused by hypoestrogenism and/or hyperandrogenism in women i ...

, and

muscle hypertrophy Muscle hypertrophy or muscle building involves a hypertrophy or increase in size of skeletal muscle through a growth in size of its component cells. Two factors contribute to hypertrophy: sarcoplasmic hypertrophy, which focuses more on increase ...

, as well as

menstrual disturbance A menstrual disorder is characterized as any abnormal condition with regards to a person's menstrual cycle. There are many different types of menstrual disorders that vary with signs and symptoms, including pain during menstruation, heavy bleeding, ...

s and reversible

infertility Infertility is the inability of a person, animal or plant to reproduce by natural means. It is usually not the natural state of a healthy adult, except notably among certain eusocial species (mostly haplodiploid insects). It is the normal state ...

. In men, the medication may also cause

testicular atrophy Testicular atrophy is a medical condition in which one or both testicles (or "testes") diminish in size and may be accompanied by reduced testicular function. Testicular atrophy is not related to the temporary shrinkage of the surrounding scrotum, ...

, and reversible infertility at sufficiently high dosages. Androstanolone can have adverse effects on the

cardiovascular system The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...

, especially with long-term administration of high dosages. AAS like androstanolone stimulate

erythropoiesis Erythropoiesis (from Greek 'erythro' meaning "red" and 'poiesis' "to make") is the process which produces red blood cells (erythrocytes), which is the development from erythropoietic stem cell to mature red blood cell. It is stimulated by decrea ...

(

red blood cell Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...

production) and increase

hematocrit The hematocrit () (Ht or HCT), also known by several other names, is the volume percentage (vol%) of red blood cells (RBCs) in blood, measured as part of a blood test. The measurement depends on the number and size of red blood cells. It is norm ...

levels and at high dosages can cause

polycythemia Polycythemia (also known as polycythaemia) is a laboratory finding in which the hematocrit (the volume percentage of red blood cells in the blood) and/or hemoglobin concentration are increased in the blood. Polycythemia is sometimes called erythr ...

(overproduction of red blood cells), which can greatly increase the risk of thrombic events such as

embolism An embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule ( fat embolism), a bubble of air or other gas (gas embolism), amniotic fluid (amniot ...

and

stroke A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...

. Unlike many other AAS, androstanolone is not

aromatized Aromatization is a chemical reaction in which an aromaticity, aromatic system is formed from a single nonaromatic precursor. Typically aromatization is achieved by dehydrogenation of existing cyclic compounds, illustrated by the conversion of cycl ...

into estrogens and hence has no risk of

ic side effects like

, fluid retention, or

edema Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...

. In addition, as it is not a 17α-alkylated AAS and is administered parenterally, androstanolone has no risk of

hepatotoxicity Hepatotoxicity (from ''hepatic toxicity'') implies chemical-driven liver damage. Drug-induced liver injury is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdrawn fro ...

. It has been theorized that androstanolone may have less risk of

benign prostatic hyperplasia Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss o ...

and

prostate cancer Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that sur ...

than testosterone because it is not aromatized into estrogens. This is relevant because estrogens are thought to possibly be necessary for the manifestation of these diseases. In accordance, androstanolone has been found to not increase

prostate gland The prostate is both an accessory gland of the male reproductive system and a muscle-driven mechanical switch between urination and ejaculation. It is found only in some mammals. It differs between species anatomically, chemically, and physio ...

size in men. Conversely, due to lack of aromatization into estrogens, androstanolone therapy for androgen replacement may result in decreased

bone mineral density Bone density, or bone mineral density, is the amount of bone mineral in bone tissue. The concept is of mass of mineral per volume of bone (relating to density in the physics sense), although clinically it is measured by proxy according to optica ...

, incomplete effects in the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...

, and undesirable changes in

cholesterol Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell mem ...

levels.

Pharmacology

Pharmacodynamics

Androstanolone is a potent

of the AR. It has an

affinity Affinity may refer to: Commerce, finance and law * Affinity (law), kinship by marriage * Affinity analysis, a market research and business management technique * Affinity Credit Union, a Saskatchewan-based credit union * Affinity Equity Par ...

(K_d) of 0.25 to 0.5 nM for the human AR, which is about 2- to 3-fold higher than that of

(K_d = 0.4 to 1.0 nM) and the dissociation rate of androstanolone from the AR is also about 5-fold slower than that of testosterone. The EC₅₀ of androstanolone for activation of the AR is 0.13 nM, which is about 5-fold stronger than that of testosterone (EC₅₀ = 0.66 nM). In

bioassay A bioassay is an analytical method to determine the concentration or potency of a substance by its effect on living animals or plants (''in vivo''), or on living cells or tissues(''in vitro''). A bioassay can be either quantal or quantitative, dir ...

s, androstanolone has been found to be 2.5- to 10-fold more potent than testosterone. Upon intramuscular injection in rats, androstanolone is about 1.5- to 2.5-fold the potency of testosterone. Unlike testosterone and various other AAS, androstanolone cannot be

, and for this reason, poses no risk of

side effect In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequence ...

s like

at any dosage. In addition, androstanolone cannot be

metabolized Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...

5α-reductase 5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of ...

(as it is already 5α-reduced), and for this reason, is not potentiated in so-called "androgenic" tissues like the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...

hair follicle The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between h ...

s, and

, thereby improving its ratio of

ic effects. However, androstanolone is nonetheless described as a very poor anabolic agent. This is attributed to its high affinity as a substrate for 3α-hydroxysteroid dehydrogenase (3α-HSD), which is highly expressed in

skeletal muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...

and inactivates androstanolone into 3α-androstanediol, a metabolite with very weak AR activity. Unlike androstanolone, testosterone is very resistant to metabolism by 3α-HSD, and so is not similarly inactivated in skeletal muscle. For the preceding reasons, androstanolone has been described as a "partial androgen".

Pharmacokinetics

Absorption

The

bioavailability In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation. By definition, when a medication is administered intravenously, its bioavailability is 100%. H ...

of androstanolone differs considerably depending on its

route of administration A route of administration in pharmacology and toxicology is the way by which a medication, drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance i ...

. Its

bioavailability is very low, and androstanolone has been considered to be ineffective by the oral route. However, it has been used orally, and is described as a weak AAS by this route. The

transdermal Transdermal is a route of administration wherein active ingredients are delivered across the skin for systemic distribution. Examples include transdermal patches used for medicine delivery. The drug is administered in the form of a patch or ointme ...

bioavailability of androstanolone is approximately 10%. Its bioavailability with

, on the other hand, is complete (100%). Doses of topical androstanolone gel of 16, 32, and 64 mg have been found to produce total testosterone and DHT levels in the low, mid, and high normal adult male range, respectively.

Distribution

The

plasma protein binding Plasma protein binding refers to the degree to which medications attach to proteins within the blood. A drug's efficiency may be affected by the degree to which it binds. The less bound a drug is, the more efficiently it can traverse or diffuse th ...

of androstanolone is about 98.5 to 99.0%. It is bound 50 to 80% to

sex hormone-binding globulin Sex hormone-binding globulin (SHBG) or sex steroid-binding globulin (SSBG) is a glycoprotein that binds to androgens and estrogens. When produced by the Sertoli cells in the seminiferous tubules of the testis, it has also been called androgen-bi ...

, 20 to 40% to

albumin Albumin is a family of globular proteins, the most common of which are the serum albumins. All the proteins of the albumin family are water-soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Albumins ...

, and less than 0.5% to

corticosteroid-binding globulin Transcortin, also known as corticosteroid-binding globulin (CBG) or serpin A6, is a protein produced in the liver in animals. In humans it is encoded by the SERPINA6 gene. It is an alpha-globulin. Function This gene encodes an alpha-globulin pro ...

, with about 1.0 to 1.5% circulating freely or unbound.

Metabolism

The

terminal half-life Biological half-life (also known as elimination half-life, pharmacologic half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the bl ...

of androstanolone in the circulation (53 minutes) is longer than that of testosterone (34 minutes), and this may account for some of the difference in their potency. A study of transdermal androstanolone and testosterone therapy reported terminal half-lives of 2.83 hours and 1.29 hours, respectively.

Chemistry

Androstanolone, also known as 5α-androstan-17β-ol-3-one or as 5α-dihydrotestosterone (5α-DHT), is a

androstane Androstane is a C19 steroidal hydrocarbon with a gonane core. Androstane can exist as either of two isomers, known as 5α-androstane and 5β-androstane. File:androstane.png, 5α-Androstane File:androstane 5beta.png, 5β-Androstane Pharmacology ...

steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...

with a ketone group at the C3 position and a

hydroxyl group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy g ...

at the C17β position. It is the

derivative In mathematics, the derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. F ...

of testosterone in which the

double bond In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist betw ...

between the C4 and C5 positions has been reduced or

hydrogenated Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic co ...

Esters

Several C17β

prodrug A prodrug is a medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be used to improve how the drug ...

s of androstanolone, including androstanolone benzoate, androstanolone enanthate,

, and

, have been developed and introduced for medical use as AAS. Conversely, dihydrotestosterone acetate, dihydrotestosterone butyrate, and dihydrotestosterone formate have been developed but have not been marketed.

Derivatives

Synthetic derivatives of androstanolone (DHT) that have been developed as AAS include: ; Non-17α-alkylated derivatives * Marketed **

Bolazine Bolazine (), also known as 2α-methyl-5α-androstan-17β-ol-3-one azine, is a synthetic androgen/anabolic steroid (AAS) of the dihydrotestosterone (DHT) group which was never marketed. It is not orally active and is used as the ester prodrug bol ...

(an

azine Azines are a functional class of organic compounds with the connectivity RR'C=N-N=CRR'. These compounds are the product of the condensation of hydrazine with ketones and aldehydes, although in practice they are often made by alternative routes ...

dimer Dimer may refer to: * Dimer (chemistry), a chemical structure formed from two similar sub-units ** Protein dimer, a protein quaternary structure ** d-dimer * Dimer model, an item in statistical mechanics, based on ''domino tiling'' * Julius Dimer ...

prodrug of drostanolone) **

Drostanolone Drostanolone, or dromostanolone, is an anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was never marketed. An androgen ester prodrug of drostanolone, drostanolone propionate, was formerly used in the treatment ...

(2α-methyl-DHT) **

Epitiostanol Epitiostanol, sold under the brand name Thiodrol, is an injection (medicine), injected antiestrogen and anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was described in the literature in 1965 and has been marketed ...

(2α,3α-epithio-DHT) **

Mepitiostane Mepitiostane, sold under the brand name Thioderon, is an oral administration, orally active antiestrogen and anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which is marketed in Japan as an antineoplastic agent for the ...

(a 17-

ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...

of epitiostanol) **

Mesterolone Mesterolone, sold under the brand name Proviron among others, is an androgen and anabolic steroid (AAS) medication which is used mainly in the treatment of low testosterone levels. It has also been used to treat male infertility, although this ...

(1α-methyl-DHT) **

Metenolone Metenolone, or methenolone, is an androgen and anabolic steroid (AAS) which is used in the form of esters such as metenolone acetate (brand name Primobolan, Nibal) and metenolone enanthate (brand name Primobolan Depot, Nibal Injection). Meten ...

(1-methyl-δ¹-DHT) ** Stenbolone (2-methyl-δ¹-DHT) * Never marketed **

1-Testosterone 1-Testosterone (abbreviated and nicknamed as 1-Testo, 1-T), also known as δ1-dihydrotestosterone (δ1-DHT), as well as dihydroboldenone, is a synthetic anabolic–androgenic steroid (AAS) and a 5α-reduced derivative of boldenone (Δ1-testo ...

(dihydroboldenone; δ¹-DHT) **

Mesabolone Mesabolone, also known as 1-testosterone 17β-methoxycyclopentyl ether, is a synthetic anabolic–androgenic steroid (AAS) that was never marketed. It is the 17β-(1-methoxycyclohexane) ether In organic chemistry, ethers are a class of comp ...

(a 17-ether prodrug of δ¹-DHT) ** Prostanozol (a 17-ether prodrug of 17α-demethylstanozolol) ; 17α-Alkylated derivatives * Marketed **

Androisoxazole Androisoxazole (brand names Androxan, Neo-Ponden, Neo-Pondus), also known as 17α-methyl-5α-androstano,2-csoxazol-17β-ol, is an orally active anabolic-androgenic steroid (AAS) and a 17α-alkylated derivative of dihydrotestosterone (DHT) that ...

(a 2,3-

isoxazole Isoxazole is an electron-rich azole with an oxygen atom next to the nitrogen. It is also the class of compounds containing this ring. Isoxazolyl is the univalent radical derived from isoxazole. Occurrence Isoxazole rings are found in some natura ...

A ring-fused derivative of 17α-methyl-DHT) **

Furazabol Furazabol (, ) (brand names Frazalon, Miotalon, Qu Zhi Shu), also known as androfurazanol, is a synthetic, orally active anabolic-androgenic steroid which has been marketed in Japan since 1969. It is a 17α-alkylated derivative of dihydrotestos ...

(a 2,3-

furan Furan is a heterocyclic organic compound, consisting of a five-membered aromatic ring with four carbon atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as furans. Furan is a colorless, flammable, highly ...

A ring-fused derivative of 17α-methyl-DHT) ** Mebolazine (an azine dimer prodrug of methasterone) **

Mestanolone Mestanolone, also known as methylandrostanolone and sold under the brand names Androstalone and Ermalone among others, is an androgen and anabolic steroid (AAS) medication which is mostly no longer used. It is still available for use in Japan ...

(17α-methyl-DHT) **

Oxandrolone Oxandrolone, sold under the brand names Oxandrin and Anavar, among others, is an androgen and anabolic steroid (AAS) medication which is used to help promote weight gain in various situations, to help offset protein catabolism caused by long-term ...

(2-oxa-17α-methyl-DHT) **

Oxymetholone Oxymetholone, sold under the brand names Anadrol and Anapolon among others, is an androgen and anabolic steroid (AAS) medication which is used primarily in the treatment of anemia. It is also used to treat osteoporosis, HIV/AIDS wasting syndrom ...

(2-hydroxymethylene-17α-methyl-DHT) **

Stanozolol Stanozolol (Abbreviation, abbrev. Stz), sold under many brand names, is an androgen and anabolic steroid (AAS) medication derived from dihydrotestosterone (DHT). It is used to treat hereditary angioedema. It was developed by American pharmaceuti ...

(a 2,3-

pyrazole Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. Pyrazole is a weak base, with p''K''b 11.5 ( ...

A ring-fused derivative of 17α-methyl-DHT) * Never marketed **

Desoxymethyltestosterone Desoxymethyltestosterone (DMT), known by the nicknames Madol and Pheraplex, is a synthetic and orally active anabolic–androgenic steroid (AAS) and a 17α-methylated derivative of dihydrotestosterone (DHT) which was never marketed for medical u ...

(3-deketo-17α-methyl-δ²-DHT) **

Methasterone Methasterone, also known as methyldrostanolone and known by the nickname Superdrol, is a synthetic and orally active anabolic–androgenic steroid (AAS) which was never marketed for medical use. It was sold legally for 9 years as a body buildi ...

(2α,17α-dimethyl-DHT) ** Methyl-1-testosterone (methyldihydroboldenone; 17α-methyl-δ¹-DHT) **

Methylepitiostanol Methylepitiostanol, known by the nicknames Epistane, Hemapolin, Havoc, and Epi Plex, is a synthetic and orally active anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was first described in the literature in 1974 b ...

(2α,3α-epithio-17α-methyl-DHT) ** Methylstenbolone (2,17α-dimethyl-δ¹-DHT)

History

Androstanolone was first discovered and synthesized in 1935 by

Adolf Butenandt Adolf Friedrich Johann Butenandt (; 24 March 1903 – 18 January 1995) was a German biochemist. He was awarded the Nobel Prize in Chemistry in 1939 for his "work on sex hormones." He initially rejected the award in accordance with government po ...

and his colleagues. It was first introduced for medical use in 1953, under the brand name ''Neodrol'' in the

, and was subsequently marketed in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...

and other

an countries. Transdermal androstanolone gel has been available in

since 1982.

Society and culture

Generic names

When used as a drug, androstanolone is referred to as ''androstanolone'' () or as ''stanolone'' () rather than as DHT.

Brand names

Brand names of androstanolone include Anaboleen, Anabolex, Anaprotin (), Andractim (formerly AndroGel-DHT) (, , ), Androlone, Apeton, Gelovit (), Neodrol, Ophtovital (), Pesomax (), Stanaprol, and Stanolone, among others.

Availability

The availability of pharmaceutical androstanolone is limited; it is not available in the

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

, but it is or has been available in certain

an countries, including the

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , i ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...

, and

Luxembourg Luxembourg ( ; lb, Lëtzebuerg ; french: link=no, Luxembourg; german: link=no, Luxemburg), officially the Grand Duchy of Luxembourg, ; french: link=no, Grand-Duché de Luxembourg ; german: link=no, Großherzogtum Luxemburg is a small lan ...

. The available formulations of androstanolone include buccal or

tablets (Anabolex, Stanolone),

topical A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...

s (Andractim, Gelovit, Ophtovital), and, as

s in

oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...

injectable An injection (often and usually referred to as a "shot" in US English, a "jab" in UK English, or a "jag" in Scottish English and Scots) is the act of administering a liquid, especially a drug, into a person's body using a needle (usually a hypo ...

s like

(Pesomax) and

(Apeton). Androstanolone benzoate (Ermalone-Amp, Hermalone, Sarcosan) and androstanolone enanthate (Anaboleen Depot) are additional androstanolone esters that are available for medical use in some countries. Androstanolone esters act as

s of androstanolone in the body and have a long-lasting

depot Depot ( or ) may refer to: Places * Depot, Poland, a village * Depot Island, Kemp Land, Antarctica * Depot Island, Victoria Land, Antarctica * Depot Island Formation, Greenland Brands and enterprises * Maxwell Street Depot, a restaurant in ...

effect when given via

Legal status

Androstanolone, along with other AAS, is a schedule III

in the

under the

Controlled Substances Act The Controlled Substances Act (CSA) is the statute establishing federal government of the United States, federal drug policy of the United States, U.S. drug policy under which the manufacture, importation, possession, use, and distribution of ...

. Androstanolone is on the

World Anti-Doping Agency The World Anti-Doping Agency (WADA; french: Agence mondiale antidopage, AMA) is a foundation initiated by the International Olympic Committee based in Canada to promote, coordinate, and monitor the fight against drugs in sports. The agency's key ...

's list of prohibited substances, and is therefore banned from use in most major sports.

Research

In the early- to mid-2000s, transdermal or topical androstanolone was under development in the

for the treatment of

(as a form of

), male

osteoporosis Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to bone fragility, and consequent increase in fracture risk. It is the most common reason for a broken bone ...

, and

cachexia Cachexia () is a complex syndrome associated with an underlying illness, causing ongoing muscle loss that is not entirely reversed with nutritional supplementation. A range of diseases can cause cachexia, most commonly cancer, congestive heart f ...

(in

cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...

patients) and in

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

for the treatment of

(BPH). It reached phase II

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, dietar ...

s for hypogonadism and BPH and phase III clinical studies for cachexia but development was ultimately never completed for these indications in these specific countries. Although androstanolone itself has not been approved for cachexia in any country, an orally active synthetic

of androstanolone,

oxandrolone Oxandrolone, sold under the brand names Oxandrin and Anavar, among others, is an androgen and anabolic steroid (AAS) medication which is used to help promote weight gain in various situations, to help offset protein catabolism caused by long-term ...

(2-oxa-17α-methylandrostanolone), is approved and used for this indication in the United States. Topical androgens like androstanolone have been used and studied in the treatment of

cellulite Cellulite is the herniation of subcutaneous fat within fibrous connective tissue that manifests as skin dimpling and nodularity, often on the pelvic region (specifically the buttocks), lower limbs, and abdomen. Cellulite occurs in most postpube ...

in women. Topical androstanolone on the abdomen has also been found to significantly decrease subcutaneous abdominal fat in women, and hence may be useful for improving body silhouette. However, men and hyperandrogenic women have higher amounts of abdominal fat than healthy women, and androgen therapy has been found to increase abdominal fat in

postmenopausal Menopause, also known as the climacteric, is the time in women's lives when menstrual periods stop permanently, and they are no longer able to bear children. Menopause usually occurs between the age of 47 and 54. Medical professionals often d ...

women and

transgender men A trans man is a man who was assigned female at birth. The label of transgender man is not always interchangeable with that of transsexual man, although the two labels are often used in this way. ''Transgender'' is an umbrella term that inclu ...

References

External links

*
Androstanolone (for hypogonadism and cachexia) - AdisInsight

Androstanolone (for hypogonadism and BPH) - AdisInsight

Androstanolone (for male osteoporosis) - AdisInsight
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Pharmacodynamics Pharmacodynamics (PD) is the study of the biochemical and physiologic effects of drugs (especially pharmaceutical drugs). The effects can include those manifested within animals (including humans), microorganisms, or combinations of organisms (fo ...

, titlestyle = background:#ccccff , list1 = {{Androgen receptor modulators {{Estrogen receptor modulators {{GABAA receptor positive allosteric modulators 5α-Reduced steroid metabolites Secondary alcohols Androgens and anabolic steroids Androstanes Estrogens GABAA receptor positive allosteric modulators Ketones Testosterone World Anti-Doping Agency prohibited substances