What is minoxidil?
Minoxidil is a medicine used to treat androgenetic alopecia (the medical term for hereditary hair loss) in both men and women. It is available in two forms: a topical solution or foam applied directly to the scalp, and a low-dose oral tablet taken by mouth.
Topical minoxidil (2% and 5%) can be purchased over the counter at pharmacies. Oral minoxidil is a prescription-only medicine, and access requires an individual medical assessment with a UK-registered prescriber.
Originally developed as a treatment for high blood pressure, minoxidil's effect on hair growth was identified as a side effect of oral use and subsequently developed into the scalp treatments available today.
How does minoxidil work?
Minoxidil is a vasodilator, meaning it works by widening blood vessels. When applied to the scalp, it is thought to increase blood flow to hair follicles, delivering more oxygen and nutrients to support hair growth. It also shortens the resting phase of the hair cycle (telogen) and prolongs the active growth phase (anagen), which encourages existing follicles to produce hair for longer.
Unlike finasteride, minoxidil does not work by targeting hormones. It does not affect dihydrotestosterone (DHT), the hormone associated with androgenetic alopecia. Instead, it acts directly on the follicle itself.
Many people notice increased shedding in the first two to six weeks of treatment. This is a normal part of the process as old hairs are pushed out to make way for new growth. It is not a sign that the treatment is not working.
Who can use minoxidil?
Topical minoxidil is suitable for men aged 18 to 65 with hereditary hair loss. It is not intended for sudden or patchy hair loss (such as alopecia areata), or where the cause of hair loss is unknown. A medical assessment is recommended in these cases.
You should not use topical minoxidil if you:
- Are allergic to minoxidil or any of its ingredients
- Have a scalp condition such as psoriasis, sunburn, or damaged skin
- Are using other topical medicines on the scalp
- Have any signs of cardiovascular disease or high blood pressure
Oral minoxidil requires a more thorough assessment. Because it is taken systemically, a UK-registered prescriber will review your cardiovascular history and blood pressure before prescribing.
Forms and dosages
Minoxidil is available in the following forms:
- Topical 5% solution or foam, applied directly to the scalp
- Oral minoxidil, a prescription-only tablet typically prescribed at up to 5 mg daily
It is worth noting that oral minoxidil for hair loss is an off-label use. It is licensed in the UK as a treatment for high blood pressure, not hair loss specifically. Your UK-registered prescriber will discuss this with you during your consultation.
How to use topical minoxidil
Apply 1 ml of solution to the affected area of the scalp twice daily (once in the morning and once in the evening). The scalp should be dry before application. Do not exceed the recommended daily amount, regardless of the size of the area being treated. Avoid wetting the scalp for at least four hours after applying.
Wash your hands thoroughly before and after applying to avoid accidental contact with other areas of the body.
Side effects and safety
Like all medicines, minoxidil can cause side effects, although not everyone experiences them.
Topical minoxidil: common side effects (may affect up to 1 in 10 people)
- Scalp irritation, itching, dryness, or redness
- Increased hair growth beyond the scalp
- Initial increase in hair shedding (temporary)
Oral minoxidil: side effects to be aware of
Oral use carries a higher risk of systemic effects due to absorption into the bloodstream. These can include:
- Fluid retention (swelling of the hands, feet, or ankles)
- Hypertrichosis (unwanted hair growth on the face and body)
- Dizziness or palpitations
- Increased heart rate
Because of these risks, oral minoxidil requires regular blood pressure monitoring during treatment. Your UK-registered prescriber will advise on the appropriate frequency.
What results can I expect, and when?
Hair loss treatments take time, and minoxidil is no exception. Most people begin to see an initial response after three to six months of consistent use. A full assessment of the treatment's effectiveness is usually made at twelve months.
It is important to continue treatment to maintain results. If minoxidil is stopped, the hair that has been retained or regrown is likely to be lost again within three to four months.
Keeping photographic records of the affected area at regular intervals is a practical way to track progress over time.
How to get minoxidil through DoktorABC
To access prescription oral minoxidil through DoktorABC, complete a confidential online health questionnaire. A UK-registered prescriber will review your responses, which will cover your cardiovascular history, current blood pressure, and any medicines you are taking. If oral minoxidil is considered appropriate, a prescription will be issued and your medication dispatched by a partner pharmacy with free next day delivery.
Important information: DoktorABC UK is a digital health platform that connects patients with independent, UK-registered prescribers. DoktorABC UK does not itself provide medical care, issue prescriptions or dispense medicines. All clinical decisions are made by the UK-registered prescriber following an individual medical assessment.
