Most men tolerate treatment well. Below is a plain-language guide to what's normal, what to monitor, and when to act — organised by medication and severity.
Not all side effects require the same response. Use this guide to know what action to take.
These are expected and typically resolve on their own. No need to stop treatment or contact your doctor unless they persist beyond 8 weeks.
Stop your medication and contact your Forme doctor through the dashboard. These effects are uncommon and typically reversible once treatment is stopped.
Stop your medication immediately and call 111 or go to your nearest emergency department. Do not wait for a Forme response.
These medications work by reducing DHT — the hormone that shrinks hair follicles. They are taken as a tablet (or applied topically in spray form). Both have well-established safety profiles backed by decades of clinical use.
A small number of men experience reduced libido, difficulty getting or maintaining an erection, or reduced ejaculate volume. These are usually temporary and typically resolve while continuing treatment or after stopping. In rare cases effects have persisted. If you experience these, stop your medication and message your doctor. Note: these effects are associated with oral finasteride; there is no conclusive evidence that topical finasteride causes the same.
Some men notice tenderness, swelling, or discharge from the nipple area. Stop treatment and seek medical advice if this occurs.
A small number of men report persistent low mood, depression, or thoughts of self-harm. If you notice a significant change in your mental health after starting treatment, stop your medication and contact your doctor promptly.
Dutasteride stays in the body longer than finasteride. If side effects occur, they may take a little longer to settle after stopping treatment.
Finasteride may affect male fertility. If you are planning to father a child, speak to your doctor about whether to continue treatment.
Finasteride is excreted in small amounts in semen, so there is a theoretical — but very low — risk that it could affect a pregnancy. Condom use is recommended if your sexual partner is pregnant.
Minoxidil increases blood flow to follicles and extends the growth phase of the hair cycle. It is available as a tablet (oral minoxidil) or as a topical spray. Side effects differ slightly between the two forms.
As minoxidil shifts follicles into a new growth cycle, resting hairs shed to make room for new growth. This is normal and expected — typically peaking around week 4 and settling by week 8. Do not stop treatment.
Topical minoxidil can cause dryness, flaking, itching, rash, or dermatitis at the application site — this usually improves within a few weeks. If applied near the face or neck it can also stimulate hair growth in those areas; apply to the scalp only and wash hands after use. If a rash or redness persists, stop using and contact your doctor.
Oral minoxidil can cause dizziness or feeling faint (low blood pressure), palpitations or a fast heartbeat, or swelling in the hands, feet or legs with shortness of breath. Contact your doctor if any of these occur, and seek urgent care if you experience chest pain.
Sudden unexplained weight gain (which may indicate fluid retention) and headache have been reported with oral minoxidil. Contact your doctor if you notice these.
This is not an exhaustive list. Talk to your doctor or pharmacist if you get any other side effects or have any concerns.
If you're a Forme patient, use the side effect reporting tool in your dashboard. Your doctor will review your report and respond — usually within one business day.
For emergencies, call 111 immediately. Do not wait for a response from Forme.