Avanafil is a

PDE5 inhibitor A phosphodiesterase type 5 inhibitor (PDE5 inhibitor) is a vasodilating drug that works by blocking the degradative action of cGMP-specific phosphodiesterase type 5 (PDE5) on cyclic GMP in the smooth muscle cells lining the blood vessels supplyi ...

approved for

erectile dysfunction Erectile dysfunction (ED), also called impotence, is the type of sexual dysfunction in which the penis fails to become or stay erect during sexual activity. It is the most common sexual problem in men.Cunningham GR, Rosen RC. Overview of male ...

by the

FDA The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...

on April 27, 2012 and by EMA on June 21, 2013. Avanafil is sold under the brand names Stendra and Spedra. It was invented at Mitsubishi Tanabe Pharma, formerly known as Tanabe Seiyaku Co., and licensed to Vivus Inc., which partnered with Menarini Group to commercialise Spedra in over forty European countries, Australia, and New Zealand. Metuchen Pharmaceuticals obtained exclusive rights within the United States. Avanafil acts by inhibiting a specific

phosphodiesterase A phosphodiesterase (PDE) is an enzyme that breaks a phosphodiester bond. Usually, ''phosphodiesterase'' refers to cyclic nucleotide phosphodiesterases, which have great clinical significance and are described below. However, there are many oth ...

type 5 enzyme found in various body tissues, primarily in the

corpus cavernosum penis A corpus cavernosum penis (singular) (literally "cave-like body" of the penis, plural corpora cavernosa) is one of a pair of sponge-like regions of erectile tissue, which contain most of the blood in the penis during an erection. Such a corpus ...

. Other similar drugs are

sildenafil Sildenafil, sold under the brand name Viagra, among others, is a medication used to treat erectile dysfunction and pulmonary arterial hypertension. It is unclear if it is effective for treating sexual dysfunction in women. It is taken by ...

tadalafil Tadalafil, sold under the brand name Cialis among others, is a medication used to treat erectile dysfunction (ED), benign prostatic hyperplasia (BPH), and pulmonary arterial hypertension. It is taken by mouth. Onset is typically within half a ...

and

vardenafil Vardenafil is a PDE5 inhibitor used for treating erectile dysfunction that is sold under the brand name Levitra among others. Medical use Vardenafil's indications and contraindications are the same as with other PDE5 inhibitors; it is closel ...

. The advantage of avanafil is that it has very fast

onset of action Onset of action is the duration of time it takes for a drug's effects to come to prominence upon administration. With oral administration, it typically ranges anywhere from 20 minutes to over an hour, depending on the drug in question. Other meth ...

compared with other PDE5 inhibitors. It is absorbed quickly, reaching a maximum serum concentration in about thirty to forty-five minutes. About two-thirds of the participants were able to engage in

sexual activity Human sexual activity, human sexual practice or human sexual behaviour is the manner in which humans experience and express their sexuality. People engage in a variety of sexual acts, ranging from activities done alone (e.g., masturbation) ...

within fifteen minutes.

Medical use

Avanafil is used to treat erectile dysfunction (ED).

Adverse effects

Although avanafil is generally well tolerated, dose dependent adverse effects can occur. The most common adverse effects include

headache Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches. Headaches can occur as a result ...

flushing Flushing may refer to: Places * Flushing, Cornwall, a village in the United Kingdom * Flushing, Queens, New York City ** Flushing Bay, a bay off the north shore of Queens ** Flushing Chinatown (法拉盛華埠), a community in Queens ** Flushing ...

nasopharyngitis The common cold or the cold is a viral infectious disease of the upper respiratory tract that primarily affects the respiratory mucosa of the nose, throat, sinuses, and larynx. Signs and symptoms may appear fewer than two days after exposu ...

nasal congestion Nasal congestion is the blockage of nasal breathing usually due to membranes lining the nose becoming swollen from inflamed blood vessels. Background In about 85% of cases, nasal congestion leads to mouth breathing rather than nasal breathing. ...

, and

back pain Back pain is pain felt in the back. It may be classified as neck pain (cervical), middle back pain (thoracic), lower back pain (lumbar) or coccydynia (tailbone or sacral pain) based on the segment affected. The lumbar area is the most common area ...

. While it is also uncommon, there is a potential for visual disturbances to occur in patients.

Mechanism of action

Avanafil inhibits phosphodiesterase-5, preventing the degradation of cGMP. The increased levels of cGMP causes

vasodilation Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstriction, ...

, resulting in an increased blood flow in the penis. Avanafil's mechanism of action takes places once

nitric oxide Nitric oxide (nitrogen oxide or nitrogen monoxide) is a colorless gas with the formula . It is one of the principal oxides of nitrogen. Nitric oxide is a free radical: it has an unpaired electron, which is sometimes denoted by a dot in its che ...

is released, in association with sexual stimulation.

Synthesis

Avanafil can be synthesized from a benzylamine derivative and a pyrimidine derivative: : Avanafil synthesis

References

External links

* {{Portal bar , Medicine Primary alcohols Carboxamides Chlorobenzenes PDE5 inhibitors Phenol ethers Aminopyrimidines Pyrrolidines Erectile dysfunction drugs Enones