Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Direct vasodilator / hair-growth stimulator

Minoxidil

Brand names: Loniten, Regaine (topical)

Minoxidil is a potent oral arterial vasodilator used for severe, treatment-resistant hypertension, usually in combination with other antihypertensives.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

Its active sulphate metabolite opens ATP-sensitive potassium channels in arteriolar smooth muscle, causing relaxation and a fall in peripheral vascular resistance and blood pressure.

Prescribing in practice

  • It causes marked fluid retention and reflex tachycardia, so it must almost always be co-prescribed with a diuretic and a beta-blocker (or other rate-controlling agent) to prevent oedema and angina.
  • Pericardial effusion, occasionally progressing to tamponade, has been reported and warrants vigilance.
  • Hypertrichosis is common and frequently leads to discontinuation, particularly in women; consult the SPC before prescribing.

Monitoring

Monitor blood pressure, heart rate, body weight and fluid status, watching for signs of pericardial effusion.

Counselling the patient

  • Warn the patient about increased growth of body and facial hair, which is reversible on stopping.
  • Advise reporting rapid weight gain, ankle swelling or breathlessness, and not to stop the medicine abruptly.

Evidence & guidelines

Oral minoxidil is reserved for resistant hypertension under specialist supervision; refer to current prescribing references.

Reference: Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways