Minoxidil side effects in women

Thinking of trying hair loss treatment? In the UK, minoxidil is the only licensed option for women.

It can come with side effects, though they’re usually nothing to worry about. Here’s what to know.

Key Takeaways

• Minoxidil is considered safe for most women.
• Side effects are common but usually not serious.
• You may be able to deal with some symptoms at home.

Is minoxidil safe for women?

Yes, minoxidil is generally considered safe for most women to use. In studies on women, both topical and oral minoxidil are well tolerated.

Common minoxidil side effects in women

Yet minoxidil can cause side effects in some people. Some of the more common side effects include:

Headache

Studies show that headaches are fairly common while using minoxidil. This is thought to be because of how it works: minoxidil improves blood flow to your hair roots, which encourages hairs to grow. But to do that, it widens your blood vessels, which may bring on a headache.

Itching or dermatitis

Topical minoxidil can irritate the skin on your scalp: it might be itchy, red, or dry.

Unwanted hair growth

Don’t forget to wash your hands after using topical minoxidil! Otherwise, you could get it on another part of your face or body by accident, which may cause unwanted hair growth.

Important: Some people experience temporary hair shedding in their first six weeks on minoxidil. This is normal: it’s because of how the medicine affects your hair growth cycle. It usually clears up on its own.

Less common side effects of minoxidil for women

These may include:

• Nausea
• Changes in hair texture

There are some side effects that are specific to oral minoxidil, including:

• Lightheadedness
• Fluid retention/swelling
• Increased heart rate
• Breast tenderness

Topical vs oral minoxidil side effects in women

Topical minoxidil works on the outside of your body: it’s applied to your skin. So, its side effects usually affect that specific area. For example, you might have an itchy scalp, which doesn’t tend to happen when you take minoxidil tablets.

On the other hand, the tablets (which are sometimes prescribed to women “off label”) are absorbed into your bloodstream and work from the inside of your body. That means they can cause more systemic symptoms, like fluid retention. It’s unlikely that enough topical minoxidil would be absorbed to cause similar systemic side effects.

Good to know: studies show that oral and topical minoxidil are similarly effective, but that the tablets are more likely to cause certain side effects. Minoxidil tablets are still considered safe for most people.

Does minoxidil affect female hormones?

Some early evidence suggests that it can. But we’re still learning about how minoxidil affects hormones, and minoxidil is not considered a hormonal treatment for hair loss.

Here’s what we know so far. Minoxidil acts on different targets in the body, including receptors for androgens (male hormones) and aromatase, an enzyme that converts androgens into oestrogen. Androgens play a role in driving hair loss.

Minoxidil may block androgens from working while increasing aromatase activity, reducing the effect of androgens on hair loss.

Ask your prescriber if you’re worried about how minoxidil might affect you. They will only suggest it if they think it’s safe for you to take.

How to deal with minoxidil side effects

Good news: you may be able to ease some minoxidil side effects at home.

• Try a cold compress for skin irritation.
• Take paracetamol or ibuprofen for a headache (neither interact with minoxidil).
• Wash your hands thoroughly after applying topical minoxidil, to prevent unwanted hair growth.
• Taking regular sips of a cold drink may help with nausea.

See your provider if your symptoms are getting worse or don’t go away.

When to see a doctor

Tell your provider if you experience:

• Chest pain
• Swelling of the face, lips, mouth, tongue, or throat (you may be having an allergic reaction)
• Low or high blood pressure
• Fast heart beat
• Dizziness, or if you feel faint
• Swelling in your hands or feet
• Unexplained weight gain
• A rash or redness that doesn’t go away

It’s always best to be safe. If you’re not sure about something or are worried, check in with your doctor. They’ll rule out anything serious.