cretion of amphetamine and may enhance the magnitude and duration of their effect. acetazolamide reduces urinary excretion of quinidine and may enhance its effect. acetazolamide may prevent the urinary antiseptic effect of methenamine. acetazolamide increases lithium excretion and the lithium may be decreased. acetazolamide and sodium bicarbonate used concurrently increases the risk of renal calculus formation. acetazolamide may elevate cyclosporine levels.

mentary effect has been noted when acetazolamide has been used in conjunction with miotics or mydriatics as the case demanded. epilepsy it is not clearly known whether the beneficial effects observed in epilepsy are due to direct inhibition of carbonic anhydrase in the central nervous system or whether they are due to the slight degree of acidosis produced by the divided dosage. the best results to date have been seen in petit mal in pediatricpatients. good results, however, have been seen in patients, both pediatricpatients and adult, in other types of seizures such as grand mal, mixed seizure patterns, myoclonic jerk patterns, etc. the suggested total daily dose is 8 mg to 30 mg per kg in divided doses. although some patients respond to a low dose, the optimum range appears to be from 375 mg to 1,000 mg daily. however, some investigators feel that daily doses in excess of 1 g do not produce any better results than a 1 g dose. when acetazolamide tablets are given in combination with other anticonvulsants, it is suggested that the starting dose should be 250 mg once daily in addition to the existing medications. this can be increased to levels as indicated above. the change from other medications to acetazolamide should be gradual and in accordance with usual practice in epilepsy therapy. congestive heart failure for diuresis in congestive heart failure, the starting dose is usually 250 mg to 375 mg once daily in the morning (5 mg/kg). if, after an initial response, the patient fails to continue to lose edema fluid, do not increase the dose but allow for kidney recovery by skipping medication for a day. acetazolamide tablets yield best diuretic results when given on alternate days, or for two days alternating with a day of rest. failures in therapy may be due to overdosage or too frequent dosage. the use of acetazolamide does not eliminate the need for other therapy such as digitalis, bed rest, and salt restriction. drug-induced edema recommended dosage is 250 to 375 mg of acetazolamide once a day for one or two days, alternating with a day of rest. acute mountain sickness dosage is 500 mg to 1,000 mg daily, in divided doses, in divided doses using tablets or sustained-release capsules as appropriate. in circumstances of rapid ascent, such as in rescue or military operations, the higher dose level of 1,000 mg is recommended. it is preferable to initiate dosing 24 hours to 48 hours before ascent and to continue for 48 hours while at high altitude, or longer as necessary to control symptoms. note: the dosage recommendations for glaucoma and epilepsy differ considerably from those for congestive heart failure, since the first two conditions are not dependent upon carbonic anhydrase inhibition in the kidney which requires intermittent dosage if it is to recover from the inhibitory effect of the therapeutic agent. interference with laboratory tests sulfonamides may give false negative or decreased values for urinary phenolsulfonphthalein and phenol red elimination values for urinary protein, serum non-protein and for serum uric acid. acetazolamide may produce an increased level of crystals in the urine. acetazolamide interferes with the hplc method of assay for theophylline. interference with the theophylline assay by acetazolamide depends on the solvent used in the extraction; acetazolamide may not interfere with other assay methods for theophylline.

pecial senses: hearing disturbances, tinnitus, transient myopia. transient myopia is the result of forward movement of the ciliary body leading to a narrowing of the angle. urogenital: crystalluria, increased risk of nephrolithiasis with long-term therapy, hematuria,

cretion of amphetamine and may enhance the magnitude and duration of their effect. acetazolamide reduces urinary excretion of quinidine and may enhance its effect. acetazolamide may prevent the urinary antiseptic effect of methenamine. acetazolamide increases lithium excretion and the lithium may be decreased. acetazolamide and sodium bicarbonate used concurrently increases the risk of renal calculus formation. acetazolamide may elevate cyclosporine levels.

ndicate that acetazolamide has utility as an adjuvant in the treatment of certain dysfunctions of the central nervous system (e.g., epilepsy). inhibition of carbonic anhydrase in this area appears to retard abnormal, paroxysmal, excessive discharge from central nervous system neurons. the diuretic effect of acetazolamide is due to its action in the kidney on the reversible reaction involving hydration of carbon dioxide and dehydration of carbonic acid. the result is renal loss of hco 3 ion, which carries out sodium, water, and potassium. alkalinization of the urine and promotion of diuresis are thus affected. alteration in ammonia metabolism occurs due to increased reabsorption of ammonia by the renal tubules as a result of urinary alkalinisation. placebo-controlled clinical trials have shown that prophylactic administration of acetazolamide at a dose of 250 mg every eight to 12 hours (or a 500 mg controlled-release capsule once daily) before and during rapid ascent to altitude results in fewer and/or less severe symptoms (such as headache, nausea, shortness of breath, dizziness, drowsiness, and fatigue) of acute mountain sickness (ams). pulmonary function (e.g., minute ventilation, expired vital capacity and peak flow) is greater in the acetazolamide treated group, both in subjects with ams and asymptomatic subjects. the acetazolamide treated climbers also had less difficulty in sleeping.

caution is advised for patients receiving concomitant high-dose aspirin and acetazolamide, as anorexia, tachypnea, lethargy, metabolic acidosis, coma and death have been reported (see warnings ). both increases and decreases in blood glucose levels have been described in patients treated with acetazolamide. this should be taken into consideration in patients with impaired glucose tolerance or diabetes mellitus. acetazolamide treatment may cause electrolyte imbalances, including hyponatremia and hypokalemia, as well as metabolic acidosis. therefore, periodic monitoring of serum electrolytes is recommended. particular caution is recommended in patients with conditions that are associated with, or predispose a patient to, electrolyte and acid/base imbalances, such as patients with impaired renal function (including elderly patients; see precautions , geriatric use ), patients with diabetes mellitus, and patients with impaired alveolar ventilation. some adverse reactions to acetazolamide, such as drowsiness, fatigue, and myopia, may impair the ability to drive and operate machinery.