Erythropoiesis-stimulating agents (ESA) are medications which stimulate the bone marrow to make red blood cells. They are used to treat anemia due to end stage kidney disease, chemotherapy, major surgery, or certain treatments in HIV/AIDS. In these situations they decrease the need for blood transfusions. The different agents are more or less equivalent. They are given by injection.Common side effects may include joint pain, rash, vomiting, and headache. Serious side effects may include heart attacks, stroke, increased cancer growth, or pure red cell aplasia. It is unclear if use is safe during pregnancy. They work similar to naturally occurring erythropoietin.They were first approved for medical use in the United States in 1989. It is on the World Health Organizations List of Essential Medicines. Commercially available agents include epoetin alfa and darbepoetin alfa, and biosimilars. Use among athletes is prohibited by the World Anti-Doping Agency. Medical uses
ESAs are used to maintain hemoglobin at the lowest level that both minimizes transfusions and best meets a persons needs. Medical speciality professional organizations do not recommend the use of ESAs in people with chronic kidney disease (CKD) who have hemoglobin levels greater than 10 g/dL and do not have anemia symptoms.
Bethanechol is a parasympathomimetic choline carbamate that selectively stimulates muscarinic receptors without any effect on nicotinic receptors. Unlike acetylcholine, bethanechol is not hydrolyzed by cholinesterase 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 resulting from general anesthetic, diabetic neuropathy of the bladder, or a side effect of antidepressants; or to treat gastrointestinal lack of muscular tone. The muscarinic receptors in the bladder and gastrointestinal tract stimulate contraction of the bladder and expulsion of urine, 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 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, coronary insufficiency, peptic ulcers, intestinal obstruction and hyperthyroidism. The parasympathomimetic action of this drug will exacerbate the symptoms of these disorders. References
External links
"Bethanechol". Drug Information Portal. U.S. National Library of Medicine.