How to Stop Hair Loss: What the Evidence Shows

Medically reviewed by Dr Mahmut Satekin, Medical Aesthetics Physician — 1 August 2026.

How to stop hair loss depends on why it is happening. Hereditary hair loss (male or female pattern hair loss) can be slowed or stopped with treatment: topical minoxidil works for both men and women, and finasteride 1 mg for men. Shedding after illness, childbirth or stress usually stops by itself within 6–9 months. Patchy hair loss (alopecia areata) needs a dermatologist, and newer prescription medicines exist for severe cases.

Key points

• Losing 50–100 hairs a day is normal.
• Treatments for hereditary hair loss work only while you use them. If you stop, the hair gained is lost within months.
• Finasteride is for men only. In the UK, the medicines regulator added warnings in 2024 about depression, suicidal thoughts and sexual side effects.
• Biotin and “hair growth” supplements have not been shown to help people who are not deficient.
• The first step is to identify the type of hair loss, not to buy a product.

Can hair loss be stopped?

Hair loss can often be stopped, but the answer depends on its type. The two most common types behave very differently.

Hereditary hair loss (androgenetic alopecia) is permanent and progressive. Hair follicles that are genetically sensitive to hormones gradually shrink. In men it shows as a receding hairline and thinning at the crown; in women as widening of the parting. It does not reverse by itself, but treatment can slow it, stop it, or partly regrow hair.

Temporary shedding (telogen effluvium) starts a few months after a trigger such as high fever, childbirth, surgery, severe stress or rapid weight loss. Once the trigger is gone, the shedding stops and hair usually returns to its normal fullness within 6–9 months (AAD).

The UK National Health Service lists the same split: permanent pattern baldness, usually hereditary, and temporary hair loss caused by illness, stress, cancer treatment, weight loss or iron deficiency (NHS).

Step 1: Find out what type of hair loss you have

Losing 50–100 hairs a day is normal (NHS). See a doctor if you notice noticeably more hair in your brush, pillow or shower for weeks, a widening part, a receding hairline, or round bald patches. Patchy loss, redness, scaling or scarring on the scalp can point to other conditions and need a dermatologist.

A doctor will usually examine the scalp, ask about recent illness, pregnancy, diet and medicines, and may order blood tests such as ferritin (iron stores), thyroid function and vitamin D.

Treatments that can stop hereditary hair loss

In the United States, the FDA has approved two medicines for hereditary hair loss: topical minoxidil and oral finasteride (Adil and Godwin, 2017). Other options are used alongside them or when they are not suitable.

Topical minoxidil

Minoxidil is applied to the scalp and is thought to lengthen the growth phase of the hair follicle. In a meta-analysis of randomised controlled trials it increased hair growth compared with placebo in men (5% and 2%) and in women (2%) (Adil and Godwin, 2017). A network meta-analysis of 33 studies found 5% minoxidil the most effective FDA-approved topical treatment in men (Gupta et al., 2025).

According to the product label, men using it twice a day may see results from 2 months, though some need at least 4 months. Shedding can increase for up to 2 weeks at the start, as new growth cycles begin. If you stop, new hair is lost within 3–4 months (FDA label). The 5% foam approved for women is used once a day, and results may be seen from month 3 (FDA label).

Finasteride 1 mg (men only)

Finasteride is a prescription tablet that lowers dihydrotestosterone (DHT), the hormone that shrinks genetically sensitive follicles. In the manufacturer’s 5-year studies of men with crown thinning, 48% of men on finasteride had increased hair growth and a further 42% had no further visible loss, compared with 6% and 19% on placebo. Daily use for at least 3 months is needed before benefit appears, and the effect reverses within 12 months of stopping (prescribing information).

Side effects are the most common concern. A meta-analysis of 15 randomised trials (4,495 men) found a 1.66 times higher risk of sexual dysfunction with finasteride (Lee et al., 2019); another meta-analysis of 17 studies found no significant difference in men treated for hair loss (Liu et al., 2016). The US label lists depression and suicidal ideation among post-marketing reports (prescribing information).

In April 2024 the UK Medicines and Healthcare products Regulatory Agency (MHRA) introduced a patient alert card and advised men taking finasteride for hair loss to stop it immediately and contact a doctor if they develop depression or suicidal thoughts; it also noted reports of sexual problems that persisted after stopping (MHRA). Women who are or may become pregnant should not handle crushed or broken tablets.

Low-dose oral minoxidil

Minoxidil taken by mouth in low doses has become more common, but it is not FDA-approved for hair loss and is prescribed at a doctor’s discretion. An analysis of 27 studies and 2,933 patients reported clear improvement in 35% of patients; most of these studies had no control group (Liu et al., 2025). The most common side effect is unwanted facial and body hair (24%); ankle swelling (2%) and light-headedness on standing (1.1%) were also reported (Jimenez-Cauhe et al., 2020). People with heart disease or blood pressure problems need careful assessment.

Spironolactone (women)

Spironolactone is an anti-androgen tablet that dermatologists prescribe off-label for female pattern hair loss. A meta-analysis reported improvement in 56.6% of women overall, higher when combined with other treatments (65.8%) than alone (43.2%), with considerable variation between studies. Reported side effects included scalp itching (18.9%), menstrual changes (11.9%) and facial hair growth (6.9%) (Aleissa, 2023). It is not used in pregnancy.

Low-level laser (red light)

Low-level laser or LED devices are a non-surgical option thought to boost energy production in the follicle. A meta-analysis of 37 studies and 3,298 patients found an average of 18.56 more hairs per square centimetre than sham devices (Alahmadi et al., 2026). Some devices have FDA clearance, which applies to the specific device (Adil and Godwin, 2017). Whether adding laser to minoxidil gives extra benefit is unclear (Alosaimi et al., 2025).

PRP (platelet-rich plasma)

PRP is plasma prepared from your own blood and injected into the scalp. Added to minoxidil, it produced an average of 17.8 more hairs per square centimetre at 5–6 months, but the certainty of this evidence was rated “low to very low” (Yao et al., 2024). Compared with minoxidil alone, PRP alone showed no significant difference in hair density (Umar et al., 2026). PRP is best seen as an add-on to medical treatment, not a replacement. More detail is on our PRP page.

How to stop hair loss from temporary shedding

Temporary shedding (telogen effluvium) usually stops on its own once the trigger has passed. What helps is finding and treating the cause. In a meta-analysis of 29 studies, people with telogen effluvium had significantly lower ferritin (iron stores) and vitamin D levels than controls (Ahmed et al., 2026). Large controlled trials showing that supplements reduce shedding are still lacking (Almohanna et al., 2019), so a blood test comes first and any deficiency is corrected under medical supervision. If shedding lasts longer than about 6 months, another cause should be looked for.

Patchy hair loss: alopecia areata

Alopecia areata is an autoimmune condition that causes round bald patches and can affect the eyebrows and eyelashes. It needs a dermatologist. For severe cases, oral JAK inhibitors are now an option: in two phase 3 trials of adults who had lost at least half their scalp hair, 38.8% and 35.9% of patients on baricitinib 4 mg had 80% or more scalp coverage at 36 weeks, compared with 6.2% and 3.3% on placebo. Acne and raised cholesterol were more common on treatment (King et al., 2022).

What does not stop hair loss

• Biotin: there is not enough evidence that biotin helps healthy people who are not deficient (Patel et al., 2017). High doses can distort some blood test results, and the FDA issued a warning about this in 2017 (ASA summary of the FDA warning). Tell your doctor if you take biotin before a blood test.
• Ketoconazole shampoo: there is no systematic-review-level evidence for hereditary hair loss; an expert consensus lists it as a supportive option only (Landells et al., 2025).
• Exosome treatments: early studies report 8–20% gains in hair density, but they are small, mostly uncontrolled, and product standards and regulation are not yet established (Malih et al., 2026).

When is a hair transplant an option?

A hair transplant moves follicles from the back of the scalp (the donor area) to thinning areas. It does not stop hereditary hair loss from progressing in the remaining native hair, which is why medical treatment is usually continued afterwards. It is considered when loss is stable, the donor area is strong enough, and expectations are realistic. Final results are usually assessed at 12–18 months.

How Hair of Istanbul assesses hair loss

At Hair of Istanbul, assessment starts with identifying the type of hair loss. The scalp is examined under magnification (trichoscopy) to record variation in hair thickness, the pattern of thinning and the condition of the donor area.

For hereditary hair loss, medical treatment is considered first, and prescription treatments are planned individually by a physician. Options such as PRP and low-level laser are offered as supportive treatments, with their level of evidence explained. Where loss is permanent and donor capacity allows, a hair transplant may be discussed. All treatments are listed on our treatments page.

Frequently asked questions

Can hair grow back after hair loss?

It depends on the type. Hair usually grows back fully after temporary shedding. In alopecia areata regrowth is possible, and prescription treatments exist for severe cases. In hereditary hair loss, treatment can regrow some hair in follicles that are shrinking but still alive; follicles that have been lost for a long time do not recover.

How long does minoxidil take to work?

Results may appear from 2 months, but some people need at least 4 months of regular use. Shedding can increase in the first 2 weeks. Benefits last only as long as you keep using it.

Is finasteride safe?

Most men in trials tolerated it, but sexual side effects occur in a minority, and regulators in the US and UK list depression and suicidal thoughts as possible risks. In the UK, men are advised to stop it and contact a doctor if mood changes appear. It should be started only after a doctor’s assessment.

Can stress cause hair loss?

Yes. Severe physical or emotional stress can trigger telogen effluvium a few months later. It is usually temporary, and hair typically recovers within 6–9 months once the stress has passed.

Which doctor should I see for hair loss?

Start with your GP or family doctor, who can arrange blood tests and refer you. Hair and scalp conditions are treated by dermatologists; see one without delay if hair loss is sudden, patchy, or comes with redness, pain or scarring.

Sources

1. American Academy of Dermatology. Do you have hair loss or hair shedding?
2. NHS. Hair loss (last reviewed 24 January 2024).
3. Adil A, Godwin M. The effectiveness of treatments for androgenetic alopecia: a systematic review and meta-analysis. J Am Acad Dermatol. 2017;77(1):136-141. doi:10.1016/j.jaad.2017.02.054
4. Gupta AK et al. J Cosmet Dermatol. 2025;24(7):e70320. doi:10.1111/jocd.70320
5. FDA. Minoxidil 5% topical solution for men, product label (NDA 020834).
6. FDA. Minoxidil 5% topical foam for women, product label (NDA 021812).
7. Finasteride 1 mg prescribing information (revised 8/2022).
8. Lee S et al. Acta Derm Venereol. 2019;99(1):12-17. doi:10.2340/00015555-3035
9. Liu L et al. J Sex Med. 2016;13(9):1297-1310. doi:10.1016/j.jsxm.2016.07.006
10. MHRA. Finasteride: reminder of the risk of psychiatric side effects and of sexual side effects (Drug Safety Update, April 2024).
11. Liu C et al. Front Pharmacol. 2025;16:1556705. doi:10.3389/fphar.2025.1556705
12. Jimenez-Cauhe J et al. Dermatol Ther. 2020;33(6):e14106. doi:10.1111/dth.14106
13. Aleissa M. The efficacy and safety of oral spironolactone in the treatment of female pattern hair loss: a systematic review and meta-analysis. Cureus. 2023;15(8):e43559. doi:10.7759/cureus.43559
14. Alahmadi M et al. Skin Appendage Disord. 2026. doi:10.1159/000551411
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19. Almohanna HM et al. Dermatol Ther (Heidelb). 2019;9(1):51-70. doi:10.1007/s13555-018-0278-6
20. King B et al. Two phase 3 trials of baricitinib for alopecia areata. N Engl J Med. 2022;386(18):1687-1699. doi:10.1056/NEJMoa2110343
21. Patel DP et al. Skin Appendage Disord. 2017;3(3):166-169. doi:10.1159/000462981
22. American Society of Anesthesiologists. FDA alert summary: Biotin may interfere with lab tests (December 2017).
23. Landells I et al. J Cutan Med Surg. 2025;29(5_suppl):5S-14S. doi:10.1177/12034754251368849
24. Malih S et al. Mol Biol Rep. 2026;53(1). doi:10.1007/s11033-026-12255-2

Medical review: Dr. Mahmut Satekin, Medical Aesthetics Physician, Hair of Istanbul. Last reviewed: 23 October 2026.

This article is for general information and does not replace diagnosis or treatment by a doctor. Medical treatment should start only after a physician’s assessment.