Acetazolamide

Acetazolamide, sold under the trade name Diamox among others, is a medication used to treat glaucoma, epilepsy, altitude sickness, periodic paralysis, idiopathic intracranial hypertension, and heart failure. It may be used long term for the treatment of open angle glaucoma and short term for acute angle closure glaucoma until surgery can be carried out. It is taken by mouth or injection into a vein. Acetazolamide, sold under the trade name Diamox among others, is a medication used to treat glaucoma, epilepsy, altitude sickness, periodic paralysis, idiopathic intracranial hypertension, and heart failure. It may be used long term for the treatment of open angle glaucoma and short term for acute angle closure glaucoma until surgery can be carried out. It is taken by mouth or injection into a vein. Common side effects include numbness, ringing in the ears, loss of appetite, vomiting, and sleepiness. It is not recommended in those with significant kidney problems, liver problems, or who are allergic to sulfonamides. Acetazolamide is in the diuretic and carbonic anhydrase inhibitor families of medication. It works by decreasing the amount of hydrogen ions and bicarbonate in the body. Acetazolamide came into medical use in 1952. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. Acetazolamide is available as a generic medication. The wholesale cost in the developing world is about US$1.40–16.93 per month. In the United States the wholesale cost is about US$125.34 per month. It is used in the treatment of glaucoma, drug-induced edema, heart failure-induced edema, epilepsy and in reducing intraocular pressure after surgery. It has also been used in the treatment of altitude sickness, Ménière's disease, increased intracranial pressure and neuromuscular disorders. In epilepsy, the main use of acetazolamide is in menstrual-related epilepsy and as an add on to other treatments in refractory epilepsy. It has been demonstrated in drug trials to relieve symptoms associated with dural ectasia in individuals with Marfan's Syndrome. A 2012 review and meta-analysis found that there was 'limited supporting evidence' but that acetazolamide 'may be considered' for the treatment of central (as opposed to obstructive) sleep apnea. It has also been used to prevent methotrexate-induced kidney damage by alkalinalizing the urine, hence speeding up methotrexate excretion by increasing its solubility in urine. In the treatment of mountain sickness, acetazolamide forces the kidneys to excrete bicarbonate, the conjugate base of carbonic acid. By increasing the amount of bicarbonate excreted in the urine, the blood becomes more acidic. As the body equates acidity of the blood to its CO2 concentration, artificially acidifying the blood fools the body into thinking it has an excess of CO2, and it excretes this imaginary excess CO2 by deeper and faster breathing, which in turn increases the amount of oxygen in the blood. Acetazolamide is not an immediate cure for acute mountain sickness; rather, it speeds up part of the acclimatization process which in turn helps to relieve symptoms. Acetazolamide is still effective if started early in the course of mountain sickness. As prevention, it is started one day before travel to altitude and continued for the first 2 days at altitude. Acetazolamide is pregnancy category B3 in Australia, which means that studies in rats, mice and rabbits in which acetazolamide was given intravenously or orally caused an increased risk of fetal malformations, including defects of the limbs. Despite this, there is insufficient evidence from studies in humans to either support or discount this evidence. Limited data are available on the effects of nursing mothers taking acetazolamide. Therapeutic doses create low levels in breast milk and are not expected to cause problems in infants.