One of the most frequently asked questions in a Farmeci hair-loss consultation is about dose. The answer is simpler than people expect — but the reasoning behind it is worth understanding, because it explains why "more" rarely means "better" in finasteride and why finasteride 5 mg, despite being widely sold, isn't the right dose for hair.

The licensed UK dose for hair loss

For male-pattern hair loss, the licensed UK dose of oral finasteride is 1 mg, once daily. This dose has been studied in large randomised trials and is the standard recommended by UK clinicians. Most men who respond to finasteride do so at this dose.

Why 5 mg isn't the hair-loss dose

The 5 mg strength of finasteride is licensed in the UK for benign prostatic hyperplasia (BPH) — enlargement of the prostate. The pharmacology is the same molecule, but BPH treatment was studied at higher doses for a different therapeutic target. Higher doses do reduce DHT slightly further than 1 mg, but trials have shown the additional hair-loss benefit is marginal at best. The clinical convention is to use the licensed dose, not the higher one.

Why higher doses don't help proportionally

Finasteride works by inhibiting 5-alpha reductase, the enzyme that converts testosterone to DHT. At 1 mg, scalp DHT is suppressed by roughly two-thirds. Pushing to 5 mg only marginally increases that suppression because the enzyme inhibition is already substantial at 1 mg. The hair follicle's response also has a ceiling — once you've blocked enough DHT to halt miniaturisation, blocking more doesn't produce proportionally more growth.

The other side of the trade-off is that side-effect frequency does increase with dose. There's no good reason to take 5 mg for hair loss when 1 mg gives nearly all the benefit.

Topical finasteride

Topical finasteride is a different proposition. It delivers the drug locally to the scalp, and absorption into circulation is meant to be lower than with oral dosing. The aim is similar suppression of scalp DHT with reduced systemic exposure. UK clinicians may prescribe topical formulations off-licence for patients who want to minimise systemic effects.

Topical dosing schedules vary by formulation — typically applied once or twice daily to the scalp. A clinician will provide specific instructions based on the product prescribed.

When to expect results

Visible response on the scalp takes time. The hair cycle is slow, and finasteride works by preventing further miniaturisation while existing follicles slowly recover. Realistic milestones:

  • 3 months: reduced shedding for many men. No visible regrowth yet.
  • 6 months: visible thickening and stabilisation for responders. Earliest point a clinician would call response.
  • 12 months: peak response. Hair counts and thickness should be at their best.

An early "dread shed" in the first weeks — increased shedding rather than reduced — is well-documented and not a sign of failure. It usually reverses as treatment progresses.

Combining with minoxidil

Combining oral finasteride with topical minoxidil targets two different mechanisms — DHT suppression and follicle stimulation — and produces better results on average than either alone. UK clinicians often suggest this combination for patients with more progressed pattern hair loss.

Working with your Farmeci clinician

A consultation will cover the pattern and timeline of your hair loss, family history, anything you've already tried, and any concerns about side effects. Dose isn't usually the variable — 1 mg daily oral or a topical preparation — but the decision about whether to start, what to combine, and when to review is individualised.