Carbonic anhydrase inhibitors adverse effects

In a 3-month prospective study of the adverse effects and efficacy of topical dorzolamide in 39 patients intolerant of systemic carbonic anhydrase inhibitors, the effect on mean intraocular pressure was similar to that of acetazolamide, and health assessment scores improved significantly in seven of the eight categories of the SF-36 health assessment questionnaire used to evaluate changes in well-being and quahty of life (4). There were no adverse effects with the switch in medication. 

Food containing salicylate (curry powder, paprika, licorice, prunes, raisins, and tea) may increase the risk of adverse reactions. Coadministration of the salicylates with activated charcoal decreases the absorption of the salicylates. Antacids may decrease the effects of the salicylates. Coadministration with the carbonic anhydrase inhibitors increases the risk of salicylism. Aspirin may increase the risk of bleeding during... 

The systemic carbonic anhydrase inhibitors are associated with significant adverse effects which include paresthesias of the hands and feet, nausea, vomiting, and weight loss. Patients... 

Adverse effects associated with brinzolamide are similar to those of other carbonic anhydrase inhibitors. In clinical experience with topical ocular administration of brinzolamide, events including transient, momentary blurred vision, bitter, and sour or unusual taste were reported in approximately 5 % - 10% of patients. Ocular discomfort, discharge or other ocular signs, and headache were reported at an incidence of 1 -5% [15]. 

All sulfonamides and their derivatives, including carbonic anhydrase inhibitors, thiazides, furosemide, bumetanide, torsemide, diazoxide, and the sulfonylurea hypoglycemic agents, are cross-allergenic. The most common adverse effects are fever, skin rashes, exfoliative dermatitis, photosensitivity, urticaria, nausea, vomiting, diarrhea, and difficulties referable to the urinary tract (see below). Stevens-Johnson syndrome, although relatively uncommon (ie, less than 1% of treatment courses), is a particularly serious and potentially fatal type of skin and mucous membrane eruption associated with sulfonamide use. Other unwanted effects include stomatitis, conjunctivitis, arthritis, hematopoietic disturbances (see Urinary Tract Disturbances), hepatitis, and, rarely, polyarteritis nodosa and psychosis. 

Of the commonly used therapeutic drugs, the greatest risks are encountered when clinicians prescribe topical steroids (for extended periods), systemic steroids, P blockers, miotic antiglaucoma agents, and oral carbonic anhydrase inhibitors (CAIs). Optometrists should be aware of the adverse effects that attend the use of these drugs and should warn patients accordingly. Disclosures should be documented in the patient record. 

The carbonic anhydrase inhibitors, of which acetazol-amide (rINN), a non-competitive inhibitor, is the prototype, are not suitable for normal diuretic use, because tolerance soon develops. However, they are well suited to brief intermittent use, particularly in the relief of glaucoma and in the prevention of acute mountain sickness. Acetazolamide and methazolamide (rINN) should be used with caution in the long-term control of glaucoma because of its serious systemic adverse effects. However, brinzolamide (rINN) and dorzolamide (rINN) are available for long-term topical administration. 

Describe the adverse effects of carbonic anhydrase inhibitors. 

Drugs that make the urine alkaline (e.g. sodium bicarbonate, carbonic anhydrase inhibitors) will reduce the elimination of memantine. Memantine should be used with caution with other NMDA antagonists, such as amantadine, ketamine and dextromethorphan, or concurrent use should be avoided, because of the theoretical increased risk of adverse effects. Memantine is predicted to interact with other drugs eliminated by the same renal secretion mechanism, but no important interaction was seen with glibenclamide, hydrochlorothiazide, metformin or triamterene. 

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