Finasteride vs minoxidil: which one do you actually need?

They're not competitors. They do different jobs.

"Finasteride or minoxidil?" is one of the most common questions men ask when they first look into hair loss treatment. It's a fair question, but it assumes the two are interchangeable options doing the same thing. They aren't.

Finasteride targets the cause of male pattern hair loss. Minoxidil supports growth at the follicle. One slows the damage, the other encourages regrowth. That's why the honest answer for a lot of men is not one or the other, but understanding what each contributes and deciding from there with a doctor.

How finasteride works.

Male pattern hair loss is driven by DHT (dihydrotestosterone), a hormone that gradually shrinks genetically sensitive hair follicles until they produce thinner, shorter hairs and eventually stop altogether. Finasteride is a daily tablet that blocks the enzyme (5-alpha reductase) that converts testosterone into DHT.

Lower DHT means the follicles stop being shrunk. For most men, the main result is that hair loss slows or stops, and a good proportion also see some regrowth over the first year. It works on the underlying process, which is why it's often considered the foundation of treatment.

Finasteride is prescription-only in New Zealand, so it always involves a doctor reviewing your health history first. Results typically take three to six months to notice, and around a year to judge properly.

How minoxidil works.

Minoxidil doesn't touch DHT at all. It was originally developed as a blood pressure medication, and hair growth was noticed as a side effect. It's thought to work by improving blood flow around the follicle and extending the growth (anagen) phase of the hair cycle, so hairs grow longer and thicker before they shed.

It comes in two forms: a topical solution or foam applied to the scalp, and a low-dose oral tablet prescribed by a doctor. Topical minoxidil is available over the counter at NZ pharmacies. Oral minoxidil requires a prescription.

Because minoxidil doesn't address DHT, the underlying process that's thinning your hair keeps going in the background. Minoxidil can outpace it for a while, but on its own it's working against the tide rather than stopping it.

So which one do you need?

Finasteride alone tends to suit men whose main goal is holding on to what they have, particularly early on when thinning is mild. It's one tablet a day and addresses the root cause.

Minoxidil alone is the usual route for men who can't or prefer not to take finasteride, for example because of side effect concerns or something in their medical history. It can still produce meaningful results, it just isn't slowing the DHT process underneath.

Both together is what the clinical evidence generally favours for the best results, because you're slowing the cause and stimulating growth at the same time. Many men start with a combined plan, especially if thinning at the crown or hairline is already noticeable.

Whichever route you take, the same rule applies to both: they only work while you use them. Stop either one and the benefit gradually fades over the following months.

Let a doctor make the call.

Reading about how each treatment works is useful, but the right choice depends on things an article can't see: your age, how far your hair loss has progressed, your medical history, other medications, and how you feel about daily tablets versus topical application.

That's what the assessment is for. It takes about two minutes, a NZ-registered doctor reviews your answers personally, and any recommendation (finasteride, minoxidil, or both) is based on your situation rather than a guess.

Take a free 2-minute assessment and get a personalised recommendation from a NZ-registered doctor.