Bethanechol is a

parasympathomimetic A parasympathomimetic drug, sometimes called a cholinomimetic drug or cholinergic receptor stimulating agent, is a substance that stimulates the parasympathetic nervous system (PSNS). These chemicals are also called cholinergic drugs because ace ...

choline Choline is an essential nutrient for humans and many other animals. Choline occurs as a cation that forms various salts (X− in the depicted formula is an undefined counteranion). Humans are capable of some ''de novo synthesis'' of choline but r ...

carbamate In organic chemistry, a carbamate is a category of organic compounds with the general formula and structure , which are formally derived from carbamic acid (). The term includes organic compounds (e.g., the ester ethyl carbamate), formall ...

that selectively stimulates muscarinic receptors without any effect on

nicotinic receptors Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral ner ...

. Unlike

acetylcholine Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Par ...

, bethanechol is not

hydrolyzed Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis ...

cholinesterase The enzyme cholinesterase (EC 3.1.1.8, choline esterase; systematic name acylcholine acylhydrolase) catalyses the hydrolysis of choline-based esters: : an acylcholine + H2O = choline + a carboxylate Several of these serve as neurotransmitters ...

and will therefore have a long duration of action. Bethanechol is sold under the brand names Duvoid (Roberts), Myotonachol (Glenwood), Urecholine (Merck Frosst) and Urocarb (Hamilton). The name bethanechol refers to its structure as the urethane of beta-methylcholine.

Medical uses

Bethanechol alleviates dry mouth and is sometimes given orally or subcutaneously to treat

urinary retention Urinary retention is an inability to completely empty the bladder. Onset can be sudden or gradual. When of sudden onset, symptoms include an inability to urinate and lower abdominal pain. When of gradual onset, symptoms may include loss of bladd ...

resulting from

general anesthetic General anaesthetics (or anesthetics, see spelling differences) are often defined as compounds that induce a loss of consciousness in humans or loss of righting reflex in animals. Clinical definitions are also extended to include an induced com ...

diabetic neuropathy Diabetic neuropathy is various types of nerve damage associated with diabetes mellitus. Symptoms depend on the site of nerve damage and can include motor changes such as weakness; sensory symptoms such as numbness, tingling, or pain; or autonomic c ...

of the bladder, or a side effect of

antidepressants Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, hea ...

; or to treat gastrointestinal lack of muscular tone. The muscarinic receptors in the

bladder The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine en ...

and

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans and ...

stimulate contraction of the bladder and expulsion of

urine Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excreted from the body through the urethra. Cellul ...

, and increased gastrointestinal motility, respectively. Bethanechol should be used to treat these disorders only after mechanical obstruction is ruled out as a possible cause. Its potential benefit in the treatment of

cerebral palsy Cerebral palsy (CP) is a group of movement disorders that appear in early childhood. Signs and symptoms vary among people and over time, but include poor coordination, stiff muscles, weak muscles, and tremors. There may be problems with sens ...

has been investigated. Atropine is given preoperatively to prevent voiding of the bowel/bladder during surgery, Bethanechol is then given postoperatively to revert this action.

Contraindications

Use of bethanechol, as well as all other muscarinic receptor agonists, is contraindicated in patients with

asthma Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, co ...

, coronary insufficiency,

peptic ulcer Peptic ulcer disease (PUD) is a break in the inner lining of the stomach, the first part of the small intestine, or sometimes the lower esophagus. An ulcer in the stomach is called a gastric ulcer, while one in the first part of the intestines ...

s, intestinal obstruction and

hyperthyroidism Hyperthyroidism is the condition that occurs due to excessive production of thyroid hormones by the thyroid gland. Thyrotoxicosis is the condition that occurs due to excessive thyroid hormone of any cause and therefore includes hyperthyroidis ...

. The parasympathomimetic action of this drug will exacerbate the symptoms of these disorders.

References

External links

* {{Portal bar , Medicine Quaternary ammonium compounds Choline esters Carbamates Muscarinic agonists Peripherally selective drugs