Carbonic anhydrase inhibitor
Carbonic anhydrase inhibitors are a class of pharmaceuticals that suppress the activity of carbonic anhydrase. Their clinical use has been established as antiglaucoma agents, diuretics, antiepileptics, in the management of mountain sickness, gastric and duodenal ulcers, neurological disorders, or osteoporosis.[1][2][3]
Contents
Medical Uses
Carbonic anhydrase inhibitors are primarily used for the treatment of glaucoma. They may also be used to treat seizure disorder and acute mountain sickness. Because they encourage solubilization and excretion of uric acid, they can be used in the treatment of gout.[4]
Glaucoma
Acetazolamide is an inhibitor of carbonic anhydrase. It is used for glaucoma, epilepsy (rarely), idiopathic intracranial hypertension, and altitude sickness.
Methazolamide is also a carbonic anhydrase inhibitor. It has a longer elimination half-life than acetazolamide and is less associated with adverse effects to the kidney.[5][6][7]
Dorzolamide is a sulfonamide and topical carbonic anhydrase II inhibitor. It is indicated for the reduction of elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension and who are insufficiently responsive to beta-blockers. Inhibition of carbonic anhydrase II in the ciliary processes of the eye decreases aqueous humor secretion, presumably by slowing the formation of bicarbonate ions with subsequent reduction in sodium and fluid transport.[citation needed]
Brinzolamide (trade names Azopt, Alcon Laboratories, Inc, Befardin Fardi Medicals) is a carbonic anhydrase inhibitor used to lower intraocular pressure in patients with open-angle glaucoma or ocular hypertension. It exists as a number of isoenzymes, the most active of which is carbonic anhydrase II (CA-II). The combination of brinzolamide with timolol is marketed under the trade name Azarga.[citation needed]
Diuretic
Acetazolamide can act as a mild diuretic by reducing NaCl and bicarbonate reabsorption in the proximal tubule. However, the distal segment partially compensates for the sodium loss, and the bicarbonaturia will produce a metabolic acidosis, further reducing the effect.
Epilepsy
Topiramate is a weak inhibitor of carbonic anhydrase, particularly subtypes II and IV. It is a sulfamate-substituted monosaccharide, related to fructose. In the US, it is approved by the U.S. Food and Drug Administration (FDA) as an anticonvulsant to treat epilepsy and Lennox-Gastaut syndrome, and also to prevent migraine headaches. In rare cases, the inhibition of carbonic anhydrase may be strong enough to cause metabolic acidosis of clinical importance.[citation needed]
Altitude Sickness
<templatestyles src="Module:Hatnote/styles.css"></templatestyles>
At high altitude, the partial pressure of oxygen is lower and people have to breathe more rapidly to get adequate oxygen. When this happens, the partial pressure of CO2 in the lungs (pCO2) decreases (is "blown off"), causing a respiratory alkalosis. This would normally be compensated by the kidney excreting bicarbonate and causing compensatory metabolic acidosis, but this mechanism takes several days. A more immediate treatment is carbonic anhydrase inhibitors, which prevent bicarbonate uptake in the kidney and help correct the alkalosis.[8] Carbonic anhydrase inhibitors have also been shown to improve chronic mountain sickness by increasing erythropoietin and the resulting polycytemia.[9]
Contraindications
Adverse effects
Loss of bicarbonate may result in metabolic acidosis.[11] Alkaline urine may increase the likelihood of kidney stones.
Natural sources
Ellagitannins extracted from the pericarps of Punica granatum, the pomegranate, such as punicalin, punicalagin, granatin B, gallagyldilactone, casuarinin, pedunculagin and tellimagrandin I, are carbonic anhydrase inhibitors.[12]
References
- ↑ Lua error in package.lua at line 80: module 'strict' not found.[page needed]
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Hyperuricemia Medication~medication at eMedicine
- ↑ Bennett WM, Aronoff GR, Golper TA, et al, Drug Prescribing in Renal Failure, American College of Physicians, Philadelphia, PA, 1987[page needed]
- ↑ Product Information: Neptazane(R), methazolamide. Storz Ophthalmics Inc, Clearwater, FL, 1995a[page needed]
- ↑ Reynolds JEF (Ed): Martle: The Extra Pharmacopoeia (electronic version). Micromedex, Inc. Englewood, CO. 1995.[page needed]
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
External links
- Carbonic anhydrase inhibitors at the US National Library of Medicine Medical Subject Headings (MeSH)
- MedlinePlus DrugInfo uspdi-202114
