ALDACTONE (Spironolactone Tablets, USP) 4 Dosage And Administration

4.2 Recommended Dose and Dosage Adjustment

1. Diagnosis and Treatment of Primary Hyperaldosteronism

   As an initial diagnostic measure to provide presumptive evidence of primary hyperaldosteronism while patients are on normal diets:

   Long Test:  Administer ALDACTONE at a daily dosage of 400 mg for 3-4 weeks.  Correction of hypokalemia and hypertension provides presumptive evidence for the diagnosis of primary hyperaldosteronism.

   Short Test:  Administer ALDACTONE at a daily dosage of 400 mg x 4 days.  If serum potassium increases or urinary potassium decreases during ALDACTONE administration, but reverts when ALDACTONE is discontinued, a presumptive diagnosis of primary hyperaldosteronism should be considered.

   After the diagnosis of primary hyperaldosteronism has been established by more definitive testing procedures, ALDACTONE may be administered in doses of 75 mg to 400 mg daily in preparation for surgery.  For those unsuitable for surgery, spironolactone may be employed for long term maintenance therapy at the lowest effective dosage determined for the individual.

2. Edematous Disorders Associated with Congestive Heart Failure, Cirrhosis and the Nephrotic Syndrome

   When given as sole agent for diuresis, continue administration for at least 5 days. If an adequate response has been achieved within 5 days, continue dosage at the same level (or in selected patients, at a reduced dosage) in either single or divided daily doses. Some may respond adequately to a dosage of only 75 mg daily. If adequate diuresis is not obtained within 5 days, a second diuretic also should be given for additive effect. Occasionally for severe resistant edema, one may add a potent glucocorticoid to this combined therapy. Normally, an initial daily dosage of 100 mg (but may range from 25 mg to 200 mg daily) of ALDACTONE administered in either single or divided doses is recommended.

   Dosage in Children (<18 years of age): The initial daily dosage should provide approximately 3 mg/kg of body weight (1.5 mg/lb) administered in either single or divided doses. This dose should be reduced to 1-2 mg/kg for maintenance therapy or combination use with other diuretics.

   Health Canada has not authorized an indication for pediatric use (see 1.1 Pediatrics)

3. Essential Hypertension

   Usually in combination with other drugs, ALDACTONE is indicated for patients who cannot be treated adequately with other agents or for whom other agents are considered inappropriate.  ALDACTONE has mild to moderate antihypertensive activity.

   For adults an initial daily dosage of 50 mg/day to 100 mg/day (in either single or divided doses) of ALDACTONE is recommended.  ALDACTONE may also be given with diuretics that act more proximally in the renal tubule or with other antihypertensive agents.  Since a stabilized response may not occur before 2 weeks, continue treatment in either single or divided daily doses for that duration of time.  Subsequently, adjust dosage in response to patient's needs.  Most patients will respond to doses not exceeding 200 mg/day.

4. Hypokalemia

   ALDACTONE in dosage ranging from 25 mg to 100 mg daily is useful in treating a diuretic induced hypokalemia, when oral potassium supplements or other potassium sparing regimens are inappropriate.  See also Table 1 for a summary of dosage recommendations.

4.5 Missed Dose

Take the missed dose as soon as you remember it. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take a double dose to make up for a missed one.