These three medicine names often appear in discussions about hair loss. Understanding the differences can help you ask informed questions. The right starting point is an assessment of the type of hair loss and your circumstances.
Start with the cause of hair loss.
Pattern hair loss, increased shedding and inflammatory scalp conditions need different approaches. A medicine used for pattern hair loss is not automatically suitable for another concern. Your history and examination help put treatment choices in context.
Minoxidil: scalp treatments and tablets.
Topical minoxidil is a liquid or foam applied to the scalp. It may help slow pattern hair loss and support growth in some people. Products and their licences differ, so the formulation and instructions need to be appropriate for the person using them.
Scalp dryness, irritation and unwanted hair growth outside the intended area can occur. Some people notice increased shedding in the early weeks. Benefits take months to assess and usually depend on continued use. The British Association of Dermatologists advises allowing at least six months before judging benefit.
What about oral minoxidil?
Minoxidil tablets are licensed for severe high blood pressure. Low-dose oral use for hair loss is outside that licence. A prescriber needs to assess suitability, other medicines and the monitoring required, including blood pressure and pulse.
Possible effects include extra facial or body hair, dizziness, palpitations and fluid retention. Chest pain, shortness of breath or fainting need urgent medical assessment. Tablets and scalp products have different risks and should be discussed individually.
Finasteride: reducing the effect of DHT.
Finasteride reduces dihydrotestosterone, or DHT, a hormone involved in male pattern hair loss. In suitable men it may slow further loss and sometimes improve growth. A response takes time, varies between individuals and depends on continuing treatment.
For hair loss, finasteride requires a private prescription in the UK. It is generally not recommended for women, although a specialist may consider it in uncommon circumstances. The prescriber must review suitability and explain the benefits and risks.
Possible side effects include reduced sex drive, erectile or ejaculation difficulties and changes in mood. Sexual problems can sometimes persist after treatment stops. The NHS also advises telling the doctor about finasteride before a PSA blood test because it can affect the result.
Dutasteride: an off-label option for hair loss.
Dutasteride also reduces DHT. Its UK licence is for an enlarged prostate, not hair loss. When prescribed for hair loss, this is an off-label use: a use outside the medicine’s marketing authorisation. It needs an individual discussion with an appropriate prescriber.
Sexual side effects and effects on semen and fertility are among the considerations. Dutasteride can also affect PSA blood-test results. Its product information includes precautions about pregnancy and contact with leaking capsules. Tell the prescriber about plans for pregnancy, fertility concerns and all other medicines.
The MHRA’s May 2026 update distinguishes the evidence for the two medicines. Finasteride is associated with psychiatric side effects; dutasteride information is being updated as a precaution because mood effects have been reported with finasteride, a medicine in the same class.
Mood changes: when to seek help.
The MHRA advises anyone taking finasteride 1 mg for hair loss to stop taking it and contact their doctor as soon as possible if depression or suicidal thoughts develop. People taking dutasteride or finasteride 5 mg should contact their doctor as soon as possible if these symptoms occur. If someone is at immediate risk of serious harm, call 999.
Questions to discuss before treatment.
- What type of hair loss is being treated, and what benefit is realistic?
- Is the proposed use licensed or off-label?
- How do your health, other medicines and any history of depression affect suitability?
- What advice applies to pregnancy, breastfeeding or plans to conceive?
- What monitoring is needed, when will treatment be reviewed, and what should you do about side effects?
This is a starting point for discussion, not a complete list of risks. Read the leaflet supplied with the specific medicine and follow the prescriber’s advice.
Where a trichology consultation fits.
A trichology assessment can help establish what is happening with your hair and scalp and explain suitable next steps. Prescription decisions, interaction checks and medical monitoring are the responsibility of an appropriately qualified prescriber. Individual treatment advice requires an assessment.
Sources & further reading
- British Association of Dermatologists: Male pattern hair loss
- British Association of Dermatologists: Female pattern hair loss
- NHS: About finasteride
- Northern Care Alliance NHS: Low-dose minoxidil for hair loss
- MHRA: Finasteride and dutasteride safety update, 11 May 2026
- Electronic Medicines Compendium: Dutasteride product information
Sources checked: 1 November 2026. General information; individual advice is given following assessment.
