minoxidil at a glance
Medicine class
Peripheral vasodilator; topical preparations stimulate hair growth.
Licensed roles
Selected scalp products treat male or female pattern hair loss; tablets treat severe hypertension.
What is minoxidil used for?
Selected licensed uses are:
Female pattern hair loss in adult women: selected foam and solution products.
Male pattern hair loss in adult men: the selected cutaneous spray solution.
Severe hypertension: oral tablets, used with other medicines to limit fluid retention and reflex tachycardia.
Specialist services sometimes prescribe oral minoxidil off-label for hair loss when topical treatment is unsuitable or ineffective.
How does minoxidil work?
For pattern hair loss, the precise mechanism is not fully understood. Minoxidil promotes the active growth phase, can increase hair-shaft diameter and improves microcirculation around follicles. Orally, it relaxes vascular smooth muscle in resistance vessels, lowering peripheral resistance; this can trigger a faster pulse and salt and water retention.
minoxidil preparations and strengths
Cutaneous foam
Route: Cutaneous
Strengths: 5% w/w
Cutaneous spray
Route: Cutaneous
Strengths: 5% w/v
Tablet
Route: Oral
Strengths: 2.5 mg, 5 mg, 10 mg
How to take minoxidil
Follow the instructions for the particular formulation; scalp products and tablets have different uses and safety requirements.
Apply topical minoxidil only to a dry, healthy scalp, not other body areas.
Avoid the eyes, damaged skin and mucous membranes; rinse accidental contact with plenty of water.
Wash hands thoroughly after applying topical products.
Avoid inhaling spray mist. Alcohol-containing spray is flammable, so keep it away from flames, lit cigarettes and heat-producing appliances while applying it.
Take tablets exactly as prescribed within supervised treatment for severe hypertension.
minoxidil side effects
Common or expected effects
- Headache.
- Scalp itching, burning, dryness, scaling, rash or dermatitis with topical products.
- Unwanted hair growth away from the scalp.
- Temporary increased hair shedding after starting topical treatment.
- Fluid retention, swelling, faster heartbeat and increased body hair with oral treatment.
Get urgent medical advice
- Severe allergic reaction or angioedema.
- Chest pain, marked palpitations, fainting or significant low blood pressure.
- Sudden weight gain, peripheral swelling or breathlessness suggesting fluid retention.
- Pericarditis, pericardial effusion or cardiac tamponade with oral treatment.
- Severe blistering, peeling or ulcerating skin reactions.
minoxidil in pregnancy
The selected topical products should not be used during pregnancy. Oral minoxidil is not recommended during pregnancy or for someone who could become pregnant and is not using contraception; human data are limited and neonatal excessive hair growth has been reported after exposure.
minoxidil interactions
Important interactions and intended companion treatments include:
Other topical scalp medicines or occlusive dressings
Concurrent use is contraindicated for the selected topical products; barrier-altering preparations may increase minoxidil absorption.
Peripheral vasodilators and other blood-pressure-lowering medicines
Blood-pressure reduction and postural dizziness may be increased.
Common questions about minoxidil
Answers are fully visible for fast scanning and source review.
What is minoxidil used for?
Selected topical products are licensed for male or female pattern hair loss, while tablets are licensed for severe hypertension.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.