Carbonic anhydrase inhibitors are pharmaceutical substances that repress the action of carbonic anhydrase — an enzyme that plays a major role in regulating pH and fluid levels in the human body. These drugs are often utilized to control glaucoma, epilepsy, and mountain sickness. They can also be used as diuretics, in the treatment of certain kinds of gastric ulcers, some neurological disorders, and osteoporosis.
To understand the role of carbonic anhydrase inhibitors in treating various diseases, it can be helpful to understand how carbonic anhydrase functions in the human body. It is largely responsible for converting carbon dioxide to carbonic acid and bicarbonate ions. Some of the tasks associated with this action are the regulation of acid levels in the stomach, and the water content in kidney and eye cells, as well as other bodily tissues. It also helps with ridding excess carbon dioxide from the body and ensuring proper pancreatic function.
When carbonic anhydrase inhibitors are used, they typically work by reducing the body’s uptake of bicarbonate ions. They also decrease salt absorption. This has the effect of lowering fluid levels in the body, hence their use as diuretic agents.
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Anti-glaucoma pharmaceuticals that are inhibitors of carbonic anhydrase include acetazolamide, dichlorphrenomide, and methazolamide, among others. These medications typically work by reducing the amount of fluid — known as aqueous humor, which is usually regulated by bicarbonate ions — that the eye produces. The most common method of administering these drugs is via eye drops. This alleviates pressure on the eye caused by glaucoma and helps to preserve vision.
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Risks associated with prolonged use of carbonic anhydrase inhibitors include kidney failure and liver disease. These drugs also tend to raise blood and urine sugar levels in diabetics. Further, these medicines can increase shortness of breath in patients suffering from emphysema.
Some of the most common side effects patients may experience when taking carbonic anhydrase inhibitors are fatigue, weakness, diarrhea, nausea, and numbness in the extremities. Some less common side effects include blood in or difficulty with urination, lower back pain, and depression. More rare side effects are hives, convulsions, and unusual bruising or bleeding, among others.
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Medical research on carbonic anhydrase inhibitors suggests that they may play a role in helping to prevent kidney cells from being attacked by certain kinds of renal cancers. This seems to be a result of these pharmaceuticals’ ability to affect pH levels. It is possible that they would be a good complementary treatment to other kinds of chemotherapy used to treat kidney cancer.