Oral minoxidil is a tablet sometimes prescribed for pattern hair loss in the UK. It is a prescription-only medicine, it is not licensed for hair loss, and it has effects on the heart and circulation that a doctor needs to weigh up before prescribing it.

This guide covers who it may and may not suit, the side effects, how it is prescribed, and what to look out for if you are thinking about seeking a prescription.

What oral minoxidil is, and why it is “off-label”

Minoxidil tablets were originally used to treat high blood pressure. The licensed UK tablet, Loniten, relaxes blood vessels so blood passes through them more easily. Its summary of product characteristics (SmPC) states that it “is indicated for the treatment of severe hypertension”, given with other medicines to control fluid retention and a faster heart rate.

Increased hair growth is a very common side effect, which is how minoxidil came to be used for hair loss. The scalp solution (Regaine) is licensed in the UK for pattern hair loss; the tablet is not. A doctor prescribing minoxidil tablets for hair loss is prescribing off-label, meaning outside the product licence, and at much lower doses than those used for blood pressure.

That puts more responsibility on the prescriber. MHRA guidance says prescribers should give patients “sufficient information about the proposed treatment, including known serious or common adverse reactions, to enable them to make an informed decision”.

Dosing. The Loniten leaflet and SmPC give doses for blood pressure, not hair loss. There is no licensed hair loss dose, so your doctor sets the dose after assessing you and reviews it over time.

Who it may suit

An NHS patient leaflet from Salford Royal Hospital’s dermatology department says patients there “are considered eligible for oral minoxidil treatment if their hair loss has not responded to topical minoxidil or if these products are not tolerated”. Whether it is appropriate for you is a clinical decision, not a preference.

Who should not take it, or needs extra caution

From the Loniten SmPC and patient leaflet:

  • Do not take it if you are allergic to minoxidil or any of the tablet’s ingredients, or if you have a phaeochromocytoma (a hormone-producing tumour, usually near the kidneys).
  • Talk to a doctor first if you have heart failure or have ever had a heart attack (the SmPC says only once the condition is stable).
  • Angina. Because minoxidil can make the heart beat faster, the SmPC warns it may bring on angina in people at risk.
  • Kidney problems, including dialysis, need particular care.
  • Other blood pressure medicines. The effect of minoxidil may add to other medicines that lower blood pressure.
  • Pregnancy and breastfeeding. The SmPC says minoxidil “is not recommended during pregnancy and in women of childbearing potential not using contraception”. It passes into breast milk.
  • Lactose. The tablets contain lactose, which matters if you have certain rare sugar intolerances.

The Salford Royal leaflet adds that people with heart problems (such as heart failure, angina or a recent heart attack), phaeochromocytoma, acute porphyria or significant kidney problems “may not be suitable”.

Side effects

The Loniten leaflet’s side effect frequencies come from people treated for high blood pressure at higher doses, so they do not translate directly to low-dose use. The Salford Royal leaflet says the risk “is reduced by using a very low dose”, and lists these as reported with oral minoxidil:

  • Unwanted hair growth on the face and body. The SmPC says this usually appears 3 to 6 weeks after starting, first on the face, and reverses one to six months after stopping.
  • Fluid retention, which can cause weight gain or ankle swelling.
  • A faster heart rate or palpitations.
  • Low blood pressure, which can cause dizziness or fainting. The Loniten leaflet says this is most likely when you first start or the dose is increased.
  • Pericarditis or pericardial effusion (inflammation of, or fluid around, the lining of the heart), which can cause chest pain or breathlessness.
  • Skin rashes, nausea and vomiting, breast tenderness, and changes in blood tests.

Initial shedding. The Salford Royal leaflet says: “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.”

When to stop and get advice

The same NHS leaflet tells patients to stop the medicine and seek advice if they notice:

  • a resting pulse more than 20 beats per minute higher than normal, or palpitations
  • rapid weight gain of more than 2 kg, or ankle swelling
  • shortness of breath or chest pain
  • dizziness, light-headedness or fainting

If you have severe chest pain, breathlessness at rest or you pass out, call 999 or go to A&E.

How prescribing works with a regulated UK service

The General Pharmaceutical Council (GPhC), which regulates pharmacies in Great Britain, explains that to obtain a prescription-only medicine online you “would need to have an appropriate consultation with a prescriber”. The medicine is then supplied by a registered pharmacy.

At WMG Meds, a service under Westminster Medical Group, 134 Harley Street, the process is:

  1. A medical questionnaire covering your date of birth, heart or blood pressure conditions, kidney and liver conditions, allergies, other medicines, and pregnancy and family planning. Under-18s are not prescribed.
  2. Review by a GMC-registered doctor, including your heart and kidney history. If oral minoxidil is not appropriate, the doctor tells you why.
  3. An explanation before any prescription. If it is suitable, the doctor explains that it is off-label, the side effects to watch for, and the dose chosen for you.
  4. Dispensing by a partner UK pharmacy, with delivery.
  5. Follow-up reviews, so the doctor can adjust or stop treatment.

The oral minoxidil product page has the full product information. If you want a doctor to assess whether it is appropriate for you, the doctor-led assessment starts with the questionnaire.

What to expect over time

Hair grows slowly, so it takes months rather than weeks to judge whether any hair loss treatment is working. In our process:

  • First weeks: a settling-in period. Some people notice the initial shed described above, which is expected.
  • Around 3 months: the first follow-up clinical review. The doctor can adjust the plan if needed.
  • Around 6 months: the plan is reviewed against your response, then reviews continue if treatment does.

Response varies from person to person, and your doctor will explain what is realistic for you.

Stopping oral minoxidil

Minoxidil leaves the blood quickly (the SmPC gives an average half-life of about 4 hours), although its effect lasts several days. Hair that was gained or kept on treatment is gradually lost over the following months, and any extra body or facial hair settles as well.

Speak to your prescriber before stopping, particularly if a side effect is the reason, because a dose change may be an option. Our guide on how to stop oral minoxidil safely covers what to expect.

Oral or topical minoxidil?

  • Topical minoxidil is applied to the scalp and its effects are mostly local, such as irritation or dryness. Regaine is licensed for pattern hair loss, and the Salford Royal leaflet describes “strong evidence” that topical minoxidil can increase hair growth.
  • Oral minoxidil is a single daily tablet with no scalp application, but it acts on the whole body, which is why the heart, blood pressure and fluid side effects above matter. The Salford Royal leaflet notes that the evidence for oral minoxidil “is less strong” than for topical.

WMG Meds also offers compounded topical minoxidil, prescribed after clinical assessment. Which route is appropriate depends on your history.

Red flags with unregulated sellers

The GPhC warns that “there are unregistered websites selling medicines that may not be genuine or haven’t been checked by a pharmacist”. Be wary if a seller:

  • offers minoxidil tablets without a consultation or prescription
  • asks nothing about your health, heart, blood pressure or other medicines
  • does not name the pharmacy that dispenses, or that pharmacy is not on the GPhC register
  • does not identify the prescriber, or the prescriber is not on the GMC register
  • offers no aftercare or way to contact a clinician if you have side effects

Frequently asked questions

Can I get oral minoxidil in the UK?

Yes, but only on prescription. It is licensed for severe high blood pressure, so for hair loss it is prescribed off-label after a clinical assessment.

What happens if I miss a tablet?

The Loniten leaflet says to miss out the forgotten dose completely, take the next dose at the normal time, and not take a double dose.

Can I drink alcohol while taking it?

The Salford Royal leaflet says alcohol may increase the risk of low blood pressure, and recommends keeping your intake down. It also notes that caffeine may increase the risk of a fast heart rate or palpitations.

Do I need to tell other doctors I am taking it?

Yes. The Loniten leaflet asks you to remind your doctor that you take it before an ECG or blood tests, as it can change the results. Tell any doctor or pharmacist before starting a new medicine.

How do I report a side effect?

Tell your prescriber. You can also report suspected side effects to the MHRA through the Yellow Card scheme.

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