Minoxidil side effects: What to expect and when to seek help

What should minoxidil do?

Minoxidil is a medically licensed treatment for androgenetic alopecia (pattern baldness). Available products include those that specifically target female pattern baldness (minoxidil for women) and male pattern baldness (minoxidil for men). It can help improve the appearance of hair loss by supporting new hair growth. 

Minoxidil is thought to support hair regrowth by helping to increase blood flow to hair follicles, which can help to stimulate hair growth and increase the growth phase of your hair cycle. 

Some increased shedding when starting treatment isn’t unusual and shouldn’t be anything to worry about. However if it persists or you’re concerned about it, stop using minoxidil and speak to your doctor, pharmacist or prescribing clinician.

How effective is minoxidil?

Minoxidil has been studied in clinical settings and may help promote hair growth in some people with pattern baldness.

Addressing pattern baldness when it first appears may improve the likelihood of seeing visible changes, although individual results will vary. People with mild to moderate hair loss may be more likely to respond where hair follicles remain active. 

It can take several months of regular use before any visible improvement is seen. Continued use is usually needed to maintain the effect, and any regrowth may be lost after stopping treatment.

How common are minoxidil side effects?

If you have no known allergies or health conditions that increase your risk of experiencing side effects, minoxidil is generally well tolerated when used as directed in your patient information leaflet. Always read the patient information leaflet of your chosen product carefully before use. 

Minoxidil may not be suitable if:

• You’re aged under 18

• You’re fully bald

• You have certain scalp conditions (such as scalp psoriasis)

• You have certain health conditions that are treated with blood pressure medication

• You’re pregnant or breastfeeding 

Minoxidil should not be used during pregnancy or breastfeeding unless specifically advised by a healthcare professional.

Check with your doctor or pharmacist before using minoxidil if any of the following apply: 

• You have a scalp condition

• You’ve had a reaction to topical treatments in the past

• You have high or low blood pressure, heart disease, or an irregular heartbeat

• You’re currently taking any blood pressure medicines

Headache is listed as a very common side effect for some topical minoxidil products, meaning it may affect more than 1 in 10 people.

Common side effects of minoxidil (experienced by up to 1 in 10 people) include:

• Hair growth in unintended areas such as the face

• Itchy scalp

Washing your hands thoroughly after application should help reduce the risk of unwanted hair growth in other areas. 

Less common side effects experienced by up to 1 in 100 people include:

• Feeling dizzy

• Feeling sick (nausea)

A rare side effect of minoxidil (affecting up to 1 in 1,000 people) is a change to the hair’s texture. If you notice this, we recommend you stop using minoxidil and speak to your pharmacist or another healthcare professional. 

This isn’t an exhaustive list of minoxidil side effects and there may be variation depending on the specific product you’re using. Always consult your patient information leaflet before starting minoxidil and check with your pharmacist, doctor or prescribing clinician if you’re unsure whether it’s suitable for you.

When to stop using minoxidil and seek medical advice

Stop using minoxidil and seek urgent medical advice if you experience chest pain, a fast or irregular heartbeat, faintness or dizziness, sudden unexplained weight gain, swelling of the hands or feet, persistent redness or irritation of the scalp, shortness of breath, or any signs of an allergic reaction such as swelling of the face, lips, mouth, tongue or throat.

You can report suspected side effects through the MHRA Yellow Card Scheme.

Who is at higher risk of experiencing side effects?

The risk of side effects from minoxidil is generally low. However, some people may be more sensitive to the active ingredient or have underlying health conditions that could affect their reaction to the product. 

People at a higher risk of experiencing side effects include those with:

• A history of allergic reactions to topical treatments 

• Dry, irritated, or sensitive skin 

• Underlying heart conditions or low blood pressure

How can the side effects of minoxidil be reduced?

To reduce possible side effects of minoxidil, follow the instructions as outlined in your patient information leaflet and do not exceed the recommended amount. Using more of the product than directed will not improve results but may increase your risk of side effects. 

Don’t apply minoxidil to irritated, inflamed, infected, damaged or broken skin unless advised by a healthcare professional.

If you do experience any side effects that cause you discomfort or disruption, stop using minoxidil and speak to your pharmacist or doctor for advice.

Is minoxidil a suitable treatment for you?

Topical minoxidil is available over the counter for some types of pattern hair loss. Other treatment options may be discussed as part of an Online Doctor consultation, where a clinician will assess what is suitable for you.

We stock a range of over-the-counter hair loss products for men and hair loss products for women in our Health & Wellness shop.