Anticonvulsants acetazolamide

Drugs that may be affected by aspirin include ACE inhibitors, acetazolamide, anticoagulants, anticonvulsants (hydantoins, valproic acid), beta blockers, diuretics, methotrexate, NSAIDs, oral hypoglycemics, and uricosuric agents (probenecid, sulfinpyrazone). 

In 1940 sulfanilamide was shown to inhibit carbonic anhydrase. It was not useful as a diuretic because the doses required to produce diuresis were excessive. Investigation of some heterocyclic sulfonamides produced some clinically effective diuretics, for example ethoxzolamide (188), but the first really useful sulfonamide diuretic was acetazolamide (189). This compound also has anticonvulsant activity which is probably related to the presence of carbonic anhydrase in the CNS. Acetazolamide had the disadvantage of producing a metabolic acidosis through the excretion of HCO3- rather than Cl and it was found that some 1,3-disulfonamidobenzenes gave a more balanced diuresis. 

Benzodiazepines - A supraspinal site of action has been demonstrated for chlordiazepoxide and diazepam as well as for meprobamate.88 xhe anticonvulsant action of chlordiazepoxide resembles that of dilantin instead of that of acetazolamide, being antagonized by reserpine but not by 0 -methyl DOPA or Ct-methyltyrosine.89 This antagonistic effect of reserpine is reduced by a-methyl DOPA, serotonin and amphetamine. The reserpine effect is thus obtained by some means other than its catecholamine-depleting action and the anticonvulsant action of chlordiazepoxide is not mediated by catecholamines. 

Acetazolamide is classified as an anticonvulsant, antiglau-comatous agent, and diuretic, and is a potent inhibitor of the enzyme carbonic anhydrase. The carbonic anhydrase inhibitors consist of acetazolamide (Diamox), ethoxzola-mide (Cardrase), and dichlorphenamide (Daranide). Acetazolamide is an old agent, whereas ethoxzolamide and dichlorphenamide are newer preparations. Dichlorphenamide is the most potent carbonic anhydrase inhibitor in use today. The presence of SO2NH2 (sulfonamide) causes such compounds to inhibit carbonic anhydrase (CA), which catalyzes the hydration of carbon dioxide as follows ... 

Mallette LE. Anticonvulsants, acetazolamide and osteomalacia. NEr lJMed(y91S) 293,668. 

Mallette LE. Acetazolamide-accelerated anticonvulsant osteomalacia. Arch Intern Med(1977) 137,1013-17. 

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