Minoxidil for women: the honest guide before you start

1 April 2026  ·  8 min read  ·  Reviewed for accuracy September 2026

I am often asked whether I am “anti-minoxidil”. I am not. It works for many women and I have recommended it. But it is sold with a great deal less honesty than it deserves, and the women who do well on it are the ones who went in knowing what to expect.

What it is and what it does

Minoxidil began life as a blood-pressure tablet whose side effect was hair growth. Applied to the scalp it widens the blood vessels around the follicle, lengthens the growing phase and pushes resting follicles into growth. Nobody fully understands why. It is licensed in the UK for female pattern hair loss as a 2% solution and a 5% foam, and it is available over the counter.

What the evidence shows

In the trials, around 40 to 60 per cent of women see a meaningful increase in hair count after six to twelve months, with the 5% foam somewhat better than the 2% solution. That is a real effect and it is why minoxidil is the reference standard against which everything else is measured. The trials also show that the gain is maintained only for as long as you keep using it.

The four things the box does not tell you loudly enough

1. The shed on starting. Between weeks two and eight, most women shed more than before. Minoxidil pushes resting follicles to restart, and to restart they first release the old hair. It is temporary and it is a sign the drug is working, but it is alarming, it happens exactly when you are most anxious, and it is the main reason women stop in the first two months. If you start, decide in advance that you will not judge it before month four.

2. The rebound on stopping. Follicles that minoxidil has been holding in growth let go when it is withdrawn. Within three to four months of stopping, most of the hair gained is shed, and some women report ending up worse than their starting point for a period. It is, in effect, a commitment for as long as you want the hair.

3. Twice a day, for ever. The solution is twice daily; the foam is once daily for women. It has to be on a dry scalp, left for four hours, and it is greasy and can make the hair look flat. Adherence is the real problem: in the studies most women drop below the effective dose within a year, and the drug does not work at half doses.

4. The side effects. Scalp irritation and flaking (the solution contains propylene glycol; the foam is better). Unwanted fine hair on the forehead, temples and cheeks in a proportion of women, from product migrating; it reverses on stopping. Occasionally headaches, dizziness or palpitations from absorption, more likely with the 5%. It is not used in pregnancy or breastfeeding.

Oral minoxidil

Low-dose minoxidil tablets (0.25 to 2.5mg) are increasingly prescribed off-label by dermatologists for women who cannot tolerate the topical, and the results are at least as good. Side effects are systemic — fluid retention, palpitations, increased body hair — and it needs a prescriber and a check of blood pressure. Not for pregnancy or feeding. Worth asking about if you have tried the topical and could not stick with it.

Who it suits

A woman with established female pattern thinning — parting, crown — who has had the treatable causes ruled out, is not planning a pregnancy, can commit to daily use indefinitely, and is prepared for the early shed. If that is you, it is a reasonable choice and the 5% foam is the version to try.

Who it does not suit

A woman with a shed that has a cause (postnatal, iron, thyroid, illness) that will resolve when the cause does; minoxidil adds a drug and a rebound to a process that was going to correct itself. A woman who is pregnant, feeding or trying. A woman who knows she will not manage daily application for years. And a woman whose thinning is at the front hairline, where minoxidil is least effective and forehead hair growth most likely.