Usual Adult Dose for Hypertension

Initial dose: 5 mg orally once a day
Maintenance dose: 10 to 40 mg per day
Maximum dose: 100 mg per day

Comments:

• Daily doses can be increased to 10, 20, and then 40 mg in single or divided doses if needed for optimum blood pressure control.
• Doses should be titrated based on individual patient response; intervals between dose adjustments should be at least 3 days; adjustments can be made every 6 hours where more rapid management of hypertension is required if patient is carefully monitored.
• If supine diastolic pressure has been reduced less than 30 mmHg, administer only once a day; if supine diastolic pressure has been reduced more than 30 mmHg, the daily dosage should be given in 2 equally divided doses.

Use: For the treatment of hypertension that is symptomatic or associated with target organ damage not manageable with maximum therapeutic doses of a diuretic plus 2 other antihypertensive drugs; use in milder hypertension not recommended as benefit to risk ratio in such patients has not been defined

Usual Pediatric Dose for Hypertension

Less than 12 years:

• Initial dose: 0.2 mg/kg orally once a day
• Maintenance 0.25 to 1 mg/kg/day
• Maximum dose: 50 mg per day

Comments:

• Doses may be increased in 50% to 100% increments until optimum blood pressure control is achieved.

Over 12 years:

• Initial dose: 5 mg orally once a day
• Maintenance dose: 10 to 40 mg per day
• Maximum dose: 100 mg per day

Comments:

• Daily doses can be increased to 10, 20, and then 40 mg in single or divided doses if needed for optimum blood pressure control.
• Doses should be titrated based on individual patient response; intervals between dose adjustments should be at least 3 days; adjustments can be made every 6 hours where more rapid management of hypertension is required if patient is carefully monitored.
• If supine diastolic pressure has been reduced less than 30 mmHg, administer only once a day; if supine diastolic pressure has been reduced more than 30 mmHg, the daily dosage should be given in 2 equally divided doses.

Use: For the treatment of hypertension that is symptomatic or associated with target organ damage not manageable with maximum therapeutic doses of a diuretic plus 2 other antihypertensive drugs; use in milder hypertension not recommended as benefit to risk ration in such patients has not been defined

Renal Dose Adjustments

Dose adjustments may be required; however, no specific guidelines have been suggested. Caution recommended. Close medical supervision to prevent exacerbation of renal failure or precipitation of cardiac failure recommended.

Liver Dose Adjustments

Data not available

Dose Adjustments

Concomitant use with a diuretic:

• Must be used in conjunction with a diuretic (e.g., hydrochlorothiazide, furosemide) in patients relying on renal function for maintaining salt and water balance.
• If excessive salt and water retention results in a weight gain of more than 5 pounds, diuretic therapy should be changed to furosemide; if the patient is already taking furosemide, dosage should be increased to meet patient requirements.

Concomitant use with a beta-blocker or other sympathetic nervous system suppressants:

• When minoxidil is begun, the dosage of a beta-adrenergic receptor blocking drug should be the equivalent of 80 to 160 mg of propranolol per day in divided doses.
• If beta-blockers are contraindicated, methyldopa (250 to 750 mg twice a day) may be used alternatively, however, must be given at least 24 hours before beginning minoxidil therapy.
• Limited clinical experience indicated clonidine at 0.1 to 0.2 mg orally twice a day may help to prevent tachycardia.

Elderly: Initiate at the low end of the dosing range due to increased likelihood for decreased hepatic, renal, or cardiac function or presence of concomitant diseases or other drug therapy.

Precautions

US BOXED WARNINGS:

• CARDIAC ADVERSE EFFECTS: This drug can cause pericardial effusion, occasionally progressing to tamponade, and angina pectoris may be exacerbated. Use should be reserved for hypertensive patients who do not respond adequately to maximum therapeutic doses of a diuretic and 2 other antihypertensive agents. In experimental animals, this drug caused several kinds of myocardial lesions as well as other adverse cardiac effects.
• CONCOMITANT THERAPY: This drug must be administered under close supervision, usually concomitantly with therapeutic doses of a beta-adrenergic blocking agent to prevent tachycardia and increased myocardial workload. It must also usually be given with a diuretic, frequently one acting in the ascending limb of the loop of Henle, to prevent serious fluid accumulation. Patients with malignant hypertension and those already receiving guanethidine should be hospitalized when minoxidil is first administered so that they can be monitored to avoid too rapid, or large orthostatic, decreases in blood pressure.

Consult WARNINGS section for additional precautions.

Dialysis

Dose adjustments may be required; however, no specific guidelines have been suggested. Caution recommended. Close medical supervision to prevent exacerbation of renal failure or precipitation of cardiac failure recommended.

Other Comments

General:

• Reduced supine diastolic blood pressure by 20 mmHg or to 90 mmHg or less in about 75% of patients, most of who had hypertension unable to be controlled by other drugs.

Monitoring:

• Metabolic: Monitor fluid and electrolyte balance and body weight closely.

Patient advice:

• Consult the patient brochure for further information

Frequently asked questions

• Does minoxidil work for beards?