Minoxidil for Hair Loss: How It Works, the Different Forms, and What to Expect

If you have started looking into hair loss treatments, Minoxidil is almost certainly one of the first names you will come across. It is the most widely used hair loss medication in the world, available in more forms than ever before, and backed by nearly four decades of clinical evidence.

But despite its long history, there is still a lot of confusion about what Minoxidil actually does, how the different forms compare, and what realistic results look like. Some men think it is a miracle cure. Others dismiss it because they tried a pharmacy bottle of Regaine for three months and did not see results.

At Magna Health, we prescribe Minoxidil every day as part of personalised treatment plans for New Zealand men. Here is the full picture — the science, the options, and the honest truth about what Minoxidil can and cannot do for your hair.

The Accidental Discovery

Minoxidil was never designed to treat hair loss. It was originally developed in the 1970s as an oral medication for severe high blood pressure, sold under the brand name Loniten. During clinical trials, doctors noticed an unexpected side effect: patients were growing hair in places they had not expected, including on their scalps [1].

Researchers quickly recognised the potential. By the late 1980s, a topical version of Minoxidil had been developed specifically for hair loss, and in August 1988, the FDA approved it under the brand name Rogaine [2]. It became the first medication ever approved for the treatment of male pattern baldness, and it has remained a cornerstone of hair loss treatment ever since.

How Minoxidil Works

Unlike Finasteride, which targets the hormonal cause of hair loss by blocking DHT, Minoxidil works by directly stimulating the hair follicle itself.

When Minoxidil is absorbed, it is converted into its active form, minoxidil sulfate. This compound opens potassium channels in the smooth muscle cells surrounding blood vessels near the hair follicle, causing them to relax and widen. The result is increased blood flow to the follicle, delivering more oxygen and nutrients to the cells responsible for hair growth [3].

But vasodilation is only part of the story. Minoxidil also appears to directly extend the anagen phase of the hair growth cycle — the active growth phase where the follicle is producing hair [4]. In men with pattern baldness, DHT progressively shortens this growth phase, causing each successive hair to come out thinner and shorter. Minoxidil counteracts this by keeping the follicle in its growth phase for longer, allowing it to produce thicker, more visible hair.

The net effect is twofold: existing miniaturised hairs become thicker and more robust, and some dormant follicles are stimulated back into active production.

The Different Forms of Minoxidil

One of the biggest changes in hair loss treatment over the past decade is the range of Minoxidil options now available. It is no longer just a bottle of liquid you rub on your scalp twice a day.

Topical Minoxidil (Solution and Foam)

This is the form most people are familiar with. Topical Minoxidil is applied directly to the scalp, typically once or twice daily. It is available over the counter in New Zealand at 2% and 5% concentrations, with the 5% formulation being significantly more effective in clinical trials [5].

The main advantage of topical application is that the medication is delivered directly where it is needed, with minimal systemic absorption. The main disadvantage is the practicality. The liquid solution can feel greasy, takes time to dry, and needs to be applied consistently to a dry scalp. The foam formulation is somewhat easier to use, but still requires daily commitment.

For men who are disciplined about their routine, topical Minoxidil is effective and well-tolerated. For men who find the daily application inconvenient or who struggle with scalp irritation from the topical formulation, there are now better alternatives.

Oral Minoxidil (Low-Dose)

Low-dose oral Minoxidil has become one of the most significant developments in hair loss treatment in recent years. Rather than applying the medication to your scalp, you take a small pill once daily — typically between 1mg and 5mg, well below the doses used for blood pressure management [6].

A 2024 randomised clinical trial published in JAMA Dermatology compared oral Minoxidil at 5mg daily against topical Minoxidil 5% in men with androgenetic alopecia. After 24 weeks, both groups showed comparable improvements in total and terminal hair density [7]. In other words, taking a daily pill produced results on par with applying a topical solution to your scalp twice a day.

A 2025 systematic review and meta-analysis of 27 studies involving 2,933 patients found that 35 percent of patients on oral Minoxidil experienced significant symptom improvement, 47 percent showed improvement, and 26 percent had stable symptoms. The treatment was particularly effective at doses exceeding 1mg [8].

The appeal of oral Minoxidil is obvious: it is simpler. One pill at night, no scalp application, no greasy residue, no waiting for it to dry. For men who want an effective, low-maintenance treatment, it has changed the game.

Compounded Topical Formulations

For many men, the most effective approach is a compounded topical formulation that combines Minoxidil with other active ingredients — most commonly Finasteride. These custom formulations are prepared by a compounding pharmacy and prescribed by a doctor as part of a tailored treatment plan.

The advantage of a combined topical spray is that you are addressing hair loss from two angles simultaneously: Minoxidil stimulates the follicle and increases blood flow, while Finasteride blocks the DHT that is causing the follicle to shrink. Delivered together in a single daily application, this combination can be more effective than either medication alone, while keeping systemic absorption lower than oral alternatives [9].

These formulations are not available off the shelf at a standard pharmacy. They require a prescription and are prepared specifically for each patient, which is one of the advantages of working with a telehealth clinic that partners with a compounding pharmacy.

The Shedding Phase: Why It Gets Worse Before It Gets Better

One of the most common reasons men abandon Minoxidil treatment prematurely is the shedding phase, sometimes referred to as the "dread shed."

Within the first two to eight weeks of starting Minoxidil, many men notice an increase in hair fall. This can be alarming, but it is actually a sign that the medication is working.

Here is what is happening: Minoxidil stimulates dormant follicles to re-enter the active growth phase. To do this, the follicle first needs to shed the old, weak, resting hair to make room for the new, thicker hair that is about to grow [10]. It is essentially a reset — the follicle pushes out the miniaturised hair and begins producing a healthier one in its place.

This shedding is temporary and self-limiting. It typically resolves within a few weeks, and the hair that grows back is thicker and stronger than what was lost. The worst thing you can do during this phase is panic and stop treatment, because you will lose the new growth that was just getting started.

What Realistic Results Look Like

Minoxidil is not a cure for hair loss, and it does not work overnight. Setting realistic expectations from the start is critical to staying on track.

The clinical data is clear: Minoxidil works for the majority of men with androgenetic alopecia. But it works best when started early, before the follicles have gone completely dormant. A follicle that is miniaturised but still active can be revived. A follicle that has shut down permanently cannot.

Side Effects: What the Evidence Says

Minoxidil has one of the longest safety records of any hair loss treatment — nearly 40 years of clinical use and extensive post-market surveillance.

For topical Minoxidil, the most common side effects are localised: scalp irritation, dryness, and flaking, particularly with the liquid solution. These are typically mild and often resolve with continued use or by switching to the foam formulation [11].

For oral Minoxidil at low doses, the most commonly reported side effect is hypertrichosis — increased hair growth on other parts of the body, such as the arms, legs, or face. A 2025 meta-analysis reported a hypertrichosis rate of approximately 35 percent in patients taking oral Minoxidil, though this was generally mild and manageable [8]. A small number of patients (approximately 4 percent) experienced minor fluid retention in the lower limbs, and instances of low blood pressure were minimal at the doses used for hair loss treatment.

Compared to many prescription medications, the side effect profile of Minoxidil is well-understood and manageable. Your prescribing doctor will assess whether Minoxidil is appropriate for your health profile and monitor your response to treatment.

Minoxidil Alone or in Combination?

For men in the early stages of hair loss, Minoxidil alone can be enough to stabilise the situation and promote regrowth. However, for men with more advanced thinning, or for those who want the most comprehensive protection, combining Minoxidil with Finasteride is the gold standard approach.

Minoxidil stimulates the follicle. Finasteride protects it by blocking the DHT that causes it to shrink. Together, they address hair loss from both sides — offence and defence. Clinical evidence consistently shows that the combination produces superior results compared to either medication used in isolation [12].

Your doctor will recommend the right approach based on the stage of your hair loss, your medical history, and your preferences around oral versus topical treatment.

Taking Action

Hair loss is progressive. The follicles you have today are easier to protect than the ones you have already lost are to revive. Whether you are noticing the first signs of thinning or you have been putting off treatment for years, the clinical evidence is clear: Minoxidil works, it is safe, and the earlier you start, the better your results will be.

At Magna Health, our registered New Zealand doctors prescribe personalised Minoxidil-based treatment plans — including oral, topical, and compounded formulations — tailored to your specific hair loss pattern and lifestyle. Your treatment is delivered discreetly to your door, with ongoing medical support included.

Start your free assessment at getmagna.co.nz

References[1] Zappacosta, A.R. (1980). Reversal of baldness in patient receiving minoxidil for hypertension. New England Journal of Medicine, 303(25), 1480-1481. https://pubmed.ncbi.nlm.nih.gov/7432404/[2] U.S. Food and Drug Administration. (1988). Minoxidil topical solution approval. https://www.accessdata.fda.gov/drugsatfda_docs/anda/2001/75-839_Minoxidil.pdf[3] Messenger, A.G. & Rundegren, J. (2004). Minoxidil: mechanisms of action on hair growth. British Journal of Dermatology, 150(2), 186-194. https://academic.oup.com/bjd/article-abstract/150/2/186/6635785[4] Gan, D.C. & Sinclair, R.D. (2005). Prevalence of male and female pattern hair loss in Maryborough. Journal of Investigative Dermatology Symposium Proceedings, 10(3), 184-189.[5] Olsen, E.A. et al. (2002). A randomized clinical trial of 5% topical minoxidil versus 2% topical minoxidil and placebo in the treatment of androgenetic alopecia in men. Journal of the American Academy of Dermatology, 47(3), 377-385. https://www.sciencedirect.com/science/article/pii/S019096220200124X[6] Godse, K. et al. (2023). Low-dose oral minoxidil in the treatment of alopecia. Indian Journal of Dermatology, 68(6), 658-663. https://pmc.ncbi.nlm.nih.gov/articles/PMC10763725/[7] Penha, M.A. et al. (2024). Oral minoxidil vs topical minoxidil for male androgenetic alopecia: a randomized clinical trial. JAMA Dermatology, 160(6), 633-640. https://jamanetwork.com/journals/jamadermatology/fullarticle/2817326[8] Liu, C. et al. (2025). Efficacy and safety of oral minoxidil in the treatment of alopecia: a single-arm rate meta-analysis and systematic review. Frontiers in Pharmacology, 16, 1556705. https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2025.1556705/full[9] Gupta, A.K. et al. (2022). Minoxidil: a comprehensive review. Journal of Dermatological Treatment, 33(4), 1896-1906. https://www.tandfonline.com/doi/abs/10.1080/09546634.2021.1945527[10] Nohria, A. et al. (2024). Combating "dread shed": The impact of overlapping topical and oral minoxidil on temporary hair shedding during oral minoxidil initiation. JAAD International, 16, 1-3. https://pmc.ncbi.nlm.nih.gov/articles/PMC11067493/[11] Medsafe New Zealand. (2026). Minoxidil — Consumer Medicine Information. https://www.medsafe.govt.nz[12] Olsen, E.A. et al. (2025). Summation and recommendations for the safe and effective use of topical and oral minoxidil. Journal of the American Academy of Dermatology. https://www.sciencedirect.com/science/article/pii/S019096222500605X