Usual Adult Dose for Congestive Heart Failure

Initial dose: 25 mg orally once a day; titrate to the target dose preferably within 4 weeks as tolerated.
Target dose: 50 mg orally once a day

Use: To improve survival of stable patients with symptomatic heart failure with reduced ejection fraction (40% or less) after an acute myocardial infarction.

Usual Adult Dose for Hypertension

Initial dose: 50 mg orally once a day
Maintenance dose: 50 mg orally once or twice a day
Maximum dose: 100 mg/day

Comments:

• Full therapeutic effect is apparent within 4 weeks.
• Patients with inadequate blood pressure response to the initial dose may be increased to 50 mg twice a day.

Renal Dose Adjustments

Heart failure post-myocardial infarction:

• CrCl greater than 30 mL/min: Dose adjustment(s) may be required; however, no specific guidelines have been suggested. Caution recommended.
• CrCl 30 mL/min or less: Contraindicated

• CrCl 50 mL/min or greater: Dose adjustment(s) may be required; however, no specific guidelines have been suggested. Caution recommended.
• CrCl less than 50 mL/min or serum creatinine greater than 1.8 mg/dL (females) or greater than 2 mg/dL (males): Contraindicated

Liver Dose Adjustments

No adjustment recommended.

Dose Adjustments

HEART FAILURE POST-MYOCARDIAL INFARCTION:
Dose Adjustments Based on Serum Potassium Level:
Less than 5 mEq/L: Increase dosage from 25 mg every other day to 25 mg once a day or from 25 mg once a day to 50 mg once a day
5 to 5.4 mEq/L: No adjustment recommended
5.5 to 5.9 mEq/L: Decrease dosage from 50 mg once a day to 25 mg once a day or from 25 mg once a day to 25 mg every other day or from 25 mg every other day to withhold
6 mEq/L or greater: Withhold; may restart at 25 mg every other day when potassium levels decrease to less than 5.5 mEq/L

Dose Adjustment for Use with Moderate CYP450 3A Inhibitors:
Maximum dose: 25 mg once a day

HYPERTENSION:
Dose Adjustment for Use with Moderate CYP450 3A Inhibitors:
Initial dose: 25 mg once a day
Maximum dose: 25 mg twice a day

Precautions

CONTRAINDICATIONS:
For all patients:

• Serum potassium greater than 5.5 mEq/L at initiation
• CrCl 30 mL/min or less
• Concomitant use with strong CYP450 3A inhibitors (e.g., ketoconazole, itraconazole, nefazodone, troleandomycin, clarithromycin, ritonavir, and nelfinavir)

• Type 2 diabetes with microalbuminuria
• Serum creatinine greater than 1.8 mg/dL in females, greater than 2 mg/dL in males
• CrCl less than 50 mL/min
• Concomitant use of potassium supplements or potassium-sparing diuretics (e.g., amiloride, spironolactone, or triamterene)

Dialysis

Data not available

Other Comments

Monitoring:

• Metabolic: Serum potassium (before starting this drug, within the first week of treatment, one month after the start of treatment or dose adjustment, and periodically thereafter); serum potassium and serum creatinine (within 3 to 7 days of starting a moderate CYP450 3A inhibitor, an angiotensin-converting enzyme (ACE) inhibitor, an angiotensin receptor blocker (ARB), or a nonsteroidal anti-inflammatory drug (NSAID).

• Advise patients not to use potassium-containing supplements or salt substitutes without consulting the prescribing physician.
• Advise patients to contact their healthcare provider if they experience dizziness, diarrhea, vomiting, rapid or irregular heartbeat, lower extremity edema, or difficulty breathing.