Dermatology - Low dose minoxidil for hair loss

What is oral minoxidil treatment?

Minoxidil is a tablet medication originally used to treat high blood pressure. Interestingly, a side effect of this tablet was the development of increased body hair growth.

This observation ultimately led to the development of a topical solution applied directly to the scalp to treat hair loss.

Topical minoxidil (known as Regaine®) is now licensed to treat male and female pattern hair loss and can be brought over the counter in most chemists.

How it improves hair growth is not fully understood but is probably due to increased blood flow to the hair roots. We see hairs growing for longer and new hair starting to grow more quickly.

In some people topical minoxidil can cause dry and tangled hair with increased hair breakage, which can be an issue particularly in fragile hair conditions.

The licensed indication for oral minoxidil is severe high blood pressure, unresponsive to standard treatment. Side effects of oral minoxidil therapy are dose related and include low blood pressure, increased heart rate and fluid retention.

Oral minoxidil for hair loss

At Salford Royal hospital, patients are considered eligible for oral minoxidil treatment if their hair loss has not responded to topical minoxidil or if these products are not tolerated. We use oral minoxidil at much lower doses than those used to treat high blood pressure, as this can still stimulate hair to grow but has a much lower risks of side effects.

How is low-dose oral minoxidil treatment given?

Minoxidil is available as a 2.5mg tablet. To achieve the correct dose of 0.625mg per day this tablet must be broken into quarters. A pill cutter will be supplied with the first prescription to enable easy cutting of the tablets.

Only take one quarter tablet per day.

Who can have oral minoxidil treatment?

You should not have this treatment if you are pregnant or trying to conceive.

All women of childbearing potential must use effective contraception during the treatment course and for 1 month after to prevent pregnancy.

A negative pregnancy test result is required before treatment can start.

People with heart problems (e.g. heart failure, angina or recent heart attack), phaeochromocytoma, acute porphyria or significant kidney problems may not be suitable for this type of treatment.

Does it work?

There is strong evidence that topical minoxidil can increase hair growth in male and female pattern hair loss. The evidence for oral minoxidil is less strong but has been used successfully in post chemotherapy hair loss, female pattern hair loss, fragile hair disorders and alopecia areata.

Are there any other treatment options available?

Yes. There are a number of reported treatments for hair loss. Feel free to discuss what alternative treatment options are available with your consultant.

Are there any risks or complications?

Yes. Although the risk of side effects is reduced by using a very low dose, the following side effects are reported with oral minoxidil:

• Fluid retention (causing weight gain and/or ankle swelling)
• Increased heart rate (fast pulse/palpitations)
• Pericarditis/pericardial effusion (causing chest pain and/or shortness of breath)
• Low blood pressure (may cause dizziness/fainting)
• Increased body hair growth
• Skin rashes
• Nausea and vomiting
• Breast tenderness
• Blood test abnormalities

You may notice some increased hair shedding at the start of treatment. Do not worry, this is very common and usually settles within 6 weeks.

For safety, your doctor will need to monitor your pulse and blood pressure at each visit, check your blood tests regularly and may also perform a heart tracing (ECG).

Can oral minoxidil be taken with my other medication?

Oral minoxidil is known to interact with a number of different medications. In particular, it can cause significant reduction in blood pressure if given with other anti-hypertensive treatments. Always inform your doctor/other health care professionals that you are taking oral minoxidil before you start any new medication. Alcohol intake may also lower your blood pressure when taken with oral monoxidil.

Do I need to change my lifestyle in any way?

We know that alcohol taken with oral minoxidil may increase the risk of low blood pressure. Therefore, we recommend you minimise your alcohol intake whilst on this treatment. Caffeine containing products (e.g. caffeinated drinks/ 'Cold & Flu' products) may increase the risk of a rapid heart rate or palpitations.

What if I develop side effects that worry me?

Before starting treatment, you will be given our contact details. You can contact us at any time during normal working hours to obtain advice or to organise an urgent review if necessary.

If you develop a worrying side effect over the weekend, you may need to seek medical advice from your local GP out of hours service.

If you are unwell and require urgent treatment you should attend your local Accident & Emergency Department.

What precautions should I take during treatment?

If you notice any of the following, please stop taking the medication and contact the department/seek emergency advice:

• Increased pulse/palpitations (>20 bpm higher than normal): Always check your pulse when resting
• Rapid weight gain (>2kg) or ankle swelling
• Shortness of breath/chest pain
• Dizziness/light-headedness/fainting

If you have problems or other unexplained symptoms, please contact the department.

Contact details

Dr Matthew Harries – email matthew.harries@nca.nhs.uk
0161 206 9880