Condition: Perte de cheveux

What It Is

Hair loss is not one condition. Five different problems share the name, they behave differently, and they respond to different treatments, so the first useful step is telling them apart:

• Androgenetic (pattern) loss is the gradual thinning most people mean. In men it recedes at the temples and thins at the crown; in women the part widens while the front hairline usually holds. It runs in families and comes on slowly.
• Telogen effluvium is the frightening handfuls in the shower two or three months after an illness, a fever, surgery, a crash diet, childbirth, or severe stress. It is a diffuse shed of the whole head that grows back once the trigger passes.
• Alopecia areata is smooth, round, sharply edged bald patches that appear over days, where the immune system attacks the follicle without destroying it.
• Traction loss is thinning along a hairline worn under tight braids, buns, weaves, or extensions.
• A medical cause shows as diffuse thinning that tracks a low iron store or a thyroid problem, and a blood test confirms it.

The scarring (cicatricial) alopecias are uncommon and the most serious form. They destroy the follicle and replace it with scar tissue, leaving smooth scalp where the tiny pore openings have vanished. That loss is permanent, and it is the one form where speed changes the outcome.

A scarred follicle never regrows, so a smooth, shiny patch with the pore openings gone is the signal to be seen quickly, while there is still hair to save.

Pattern loss responds best when treatment starts early, before too much is gone. This guide covers the treatments that regrow or hold hair, the large market of products that do not, and the signs that call for a doctor.

What slows and reverses it

The findings below are ordered with the strongest evidence first. Pattern loss is treated for the long term: the regained hair depends on the treatment continuing, and stopping lets the loss resume within months.

For pattern loss, start with topical minoxidil. Its evidence is the strongest of the topicals, about 13 more hairs per cm2 in the pooled trials, it needs no prescription, and it works for both men and women. It works by a different route than the hormone drugs, so it combines with them. For men, finasteride taken as a daily tablet is the second mainstay, often used alongside minoxidil. Dutasteride is its stronger relative, kept in reserve for men in whom finasteride has not done enough. A low-dose minoxidil tablet has moved quickly into mainstream practice and suits people who dislike the daily liquid, though it acts on the whole body and needs a prescriber.

For extensive alopecia areata, the oral JAK inhibitors carry the strongest evidence. Phase 3 trials showed near-complete regrowth for a substantial share of people, a marked advance over what came before. They are specialist-prescribed and monitored with blood tests. For a few small patches, steroid injections are the long-standing first move, resting more on decades of practice than on controlled trials.

Two of the findings involve no medication. Telogen effluvium, the heavy diffuse shed after a shock to the body, resolves on its own once the trigger passes. A low iron store can drive diffuse shedding, especially in women, so a ferritin blood test is a reasonable step. Iron is worth taking only if the test shows a deficiency. Platelet-rich plasma injections and laser caps both beat their placebos in pooled trials on uneven, low-quality evidence, so they sit as possible add-ons for someone already on the proven treatments.

The Research & Studies

Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.

Skin And Hair

Le minoxidil topique ajoute environ 13 cheveux par cm2 dans la perte de type androgénétiqueStrong

In plain terms

Le minoxidil appliqué sur le cuir chevelu est la première étape éprouvée pour la perte de cheveux de type androgénétique, chez les hommes comme chez les femmes. Il ralentit l'amincissement et fait repousser une partie des cheveux, et il faut le poursuivre, car le bénéfice s'estompe dans les mois suivant l'arrêt.

In detail

Le minoxidil est le traitement topique le mieux étayé pour l'alopécie androgénétique. La méta-analyse de 2017 d'Adil et Godwin a trouvé que le minoxidil à 5 % et à 2 % étaient chacun supérieurs au placebo dans l'ensemble des essais regroupés (P < 0.00001). La revue Cochrane de 2016 sur la perte de cheveux de type féminin a trouvé que davantage de femmes sous minoxidil rapportaient au moins une augmentation modérée de la repousse que sous placebo (risque relatif 1.93) et un gain moyen d'environ 13 cheveux par cm2. L'effet est modeste et dépendant de la dose, et il ne se maintient que tant que le traitement se poursuit.

How to use it

Appliquez-le quotidiennement et laissez six à douze mois avant d'en juger, et attendez-vous à quelques premières semaines de chute supplémentaire pendant que le cycle se réinitialise. Arrêter signifie que les cheveux regagnés sont à nouveau perdus, il faut donc le considérer comme un traitement continu.

The studies · 2

Adil & Godwin, The effectiveness of treatments for androgenetic alopecia: a systematic review and meta-analysis · J Am Acad Dermatol 2017;77(1):136-141.e5

van Zuuren et al., Interventions for female pattern hair loss (Cochrane review) · Cochrane Database Syst Rev 2016;(5):CD007628

Counts once: this finding and 2 others here come from the same source, so they are one body of evidence, not separate confirmations.

Daily finasteride slows male pattern loss and regrows some hairStrong

In plain terms

Chez les hommes, un comprimé quotidien de finastéride ralentit la perte de type androgénétique et fait repousser une partie des cheveux en bloquant l'hormone qui rétrécit le follicule. C'est l'un des deux piliers avec le minoxidil, et les deux sont souvent utilisés ensemble.

In detail

Finasteride blocks the conversion of testosterone to dihydrotestosterone, the androgen that miniaturizes scalp follicles in genetically susceptible men. The 2017 systematic review and meta-analysis by Adil and Godwin found finasteride 1 mg superior to placebo (P < .00001). The 2022 JAMA Dermatology network meta-analysis by Gupta and colleagues compared the oral 5-alpha-reductase inhibitors and minoxidil head-to-head across 24 and 48 weeks and found topical or oral minoxidil and dutasteride edged finasteride on some endpoints. An earlier network meta-analysis by the same group reached a favorable benefit-risk conclusion for the 5-alpha-reductase inhibitors as a class.

Who this may not transfer to:Oral finasteride is licensed and studied for men. In women it was no more effective than placebo (see the finasteride-in-women row), and it is avoided in women who could become pregnant.

How to use it

Effects build over six to twelve months and reverse if the drug is stopped, so it is a long-term commitment. Combining it with topical minoxidil generally does better than either alone.

The studies · 3

Adil & Godwin, The effectiveness of treatments for androgenetic alopecia: a systematic review and meta-analysis · J Am Acad Dermatol 2017;77(1):136-141.e5

Gupta et al., Relative efficacy of minoxidil and the 5-alpha reductase inhibitors in androgenetic alopecia treatment of male patients: a network meta-analysis · JAMA Dermatol 2022;158(3):266-274

Gupta et al., The efficacy and safety of 5-alpha reductase inhibitors in androgenetic alopecia: a network meta-analysis and benefit-risk assessment · J Dermatolog Treat 2014;25(2):156-161

Counts once: this finding and 2 others here come from the same source, so they are one body of evidence, not separate confirmations.

JAK inhibitors regrow the scalp for about 36 to 39% in severe alopecia areataStrong

In plain terms

For extensive alopecia areata, the newer oral JAK inhibitors regrow hair for a substantial share of people, a marked change from what was available before. They work while taken and the hair tends to fall out again if they are stopped.

In detail

Alopecia areata is autoimmune, and JAK inhibitors interrupt the immune signaling that attacks the follicle. The BRAVE-AA1 and BRAVE-AA2 phase 3 trials of baricitinib (King et al., 2022) showed roughly 36 to 39% of patients on the 4 mg dose reached a SALT score of 20 or less, meaning at least 80% scalp coverage, against 3 to 6% on placebo. The 2023 Cochrane meta-analysis rated baricitinib high-certainty for both short- and long-term regrowth and ranked JAK inhibitors as the most effective class. Ritlecitinib is also approved. Benefit depends on continued treatment, and the drugs carry class risks including infection and blood-count and lipid changes, so they are specialist-prescribed and monitored.

How to use it

These are for extensive or fast-moving alopecia areata under a dermatologist, with baseline and ongoing blood tests and an understanding that the hair usually needs the drug to stay.

The studies · 2

King et al., Two phase 3 trials of baricitinib for alopecia areata (BRAVE-AA1 and BRAVE-AA2) · N Engl J Med 2022;386(18):1687-1699

Mateos-Haro et al., Treatments for alopecia areata: a network meta-analysis (Cochrane review) · Cochrane Database Syst Rev 2023;10(10):CD013719

Counts once: this finding and 1 other here come from the same source, so they are one body of evidence, not separate confirmations.

Dutasteride regrows about 7.1 more hairs per cm2 than finasterideModerate

In plain terms

Dutasteride, a stronger relative of finasteride, regrows a little more hair than finasteride in men. It is used off-label for hair loss and is the more potent of the two 5-alpha-reductase inhibitors.

In detail

Dutasteride blocks both forms of the 5-alpha-reductase enzyme where finasteride blocks mainly one, and it lowers scalp dihydrotestosterone further. The 2022 meta-analysis found dutasteride 0.5 mg the top-ranked oral agent, beating finasteride 1 mg by roughly 7.1 hairs per cm2 at 24 weeks. It is not licensed for hair loss in most countries and carries the same class of sexual side effects, so it is generally a second step when finasteride has not done enough.

Who this may not transfer to:Studied in men; not established for women and avoided in women who could become pregnant.

How to use it

Reserve it for men in whom finasteride has underperformed, and weigh the modest extra gain against the same sexual side-effect profile and its off-label status.

The study · 1

Gupta et al., Relative efficacy of minoxidil and the 5-alpha reductase inhibitors in androgenetic alopecia treatment of male patients: a network meta-analysis · JAMA Dermatol 2022;158(3):266-274

Counts once: this finding and 1 other here come from the same source, so they are one body of evidence, not separate confirmations.

Finasteride does not beat placebo in women with pattern lossModerate · no effect

In plain terms

Finasteride, the mainstay for men, did not beat placebo in women with pattern loss in the pooled trials. For women the proven drug is minoxidil, and finasteride is also avoided in those who could become pregnant.

In detail

The 2016 Cochrane review by van Zuuren and colleagues assessed interventions for female pattern hair loss and concluded that finasteride was not more effective than placebo in women, in contrast to its clear effect in men. This reflects the different hormonal drivers of the condition between the sexes. Finasteride is additionally contraindicated in women who may become pregnant because of the risk to a male fetus. Some specialists still use it in specific post-menopausal cases, but the trial evidence for benefit in women is absent.

Who this may not transfer to:In men the same drug clearly works, so this no-effect finding is specific to women, not a weakness of the drug overall.

How to use it

In women, reach for minoxidil first. If an anti-androgen is being considered, that is a specialist conversation, and finasteride is not used where pregnancy is possible.

The study · 1

van Zuuren et al., Interventions for female pattern hair loss (Cochrane review) · Cochrane Database Syst Rev 2016;(5):CD007628

Counts once: this finding and 1 other here come from the same source, so they are one body of evidence, not separate confirmations.

La biotine ne fait rien pour les cheveux en l'absence de carenceModerate · no effect

In plain terms

Biotin helps hair only if you are truly deficient in it, which is uncommon. For everyone else it does nothing measurable, and it can also throw off some lab tests, including thyroid and heart blood tests.

In detail

La revue de 2017 par Patel et ses collègues a constaté que chaque cas publié de biotine aidant les cheveux ou les ongles impliquait un patient présentant un déficit sous-jacent, allant de troubles enzymatiques héréditaires à une mauvaise absorption, un total de 18 rapports. Il n'existe aucune preuve contrôlée que la biotine aide les cheveux chez les personnes avec des taux normaux, et la véritable carence est rare avec une alimentation normale. La biotine interfère également avec certains immunoessais et peut produire des résultats faussement élevés ou bas sur les tests thyroïdiens, hormonaux et de troponine, un point de sécurité compte tenu de son intense commercialisation. Les revues sur les vitamines et minéraux arrivent à la même conclusion prudente pour les suppléments capillaires en général sans carence documentée.

How to use it

Éviter la biotine pour les cheveux à moins qu'une carence n'ait été confirmée, et si vous en prenez, informez tout médecin prescrivant des analyses sanguines, car elle peut fausser les résultats thyroïdiens et cardiaques.

The studies · 2

Patel et al., A review of the use of biotin for hair loss · Skin Appendage Disord 2017;3(3):166-169

Almohanna et al., The role of vitamins and minerals in hair loss: a review · Dermatol Ther (Heidelb) 2019;9(1):51-70

Low-dose oral minoxidil works about as well as the topical solutionEmerging

In plain terms

A low-dose minoxidil tablet works about as well as the scalp solution and suits people who dislike the daily liquid or find it irritating. It is a fast-growing off-label option, not a licensed treatment.

In detail

Low-dose oral minoxidil (commonly 0.25 to 5 mg daily) has moved quickly from niche to mainstream in dermatology. The 2024 JAMA Dermatology trial by Penha and colleagues compared oral against topical minoxidil head-to-head in men and found no significant difference in hair density at 24 weeks, with a non-significant trend favoring the tablet at the vertex. It avoids the mess and scalp irritation of the solution but is systemic, so it can cause unwanted body-hair growth, fluid retention and, uncommonly, effects on the heart, which is why it is prescribed and monitored.

Who this may not transfer to:This trial was in men. Low-dose oral minoxidil is also widely used in women, but this comparison did not test them.

How to use it

Because it acts on the whole body, it belongs with a prescriber who can screen for heart and blood-pressure issues and watch for excess body hair and swelling; it is not something to source and self-dose.

The study · 1

Penha et al., Oral minoxidil vs topical minoxidil for male androgenetic alopecia: a randomized clinical trial · JAMA Dermatol 2024;160(6):600-605

Platelet-rich plasma adds about 25.6 hairs per cm2 on low-quality evidenceEmerging

In plain terms

Injecting your own concentrated platelets into the scalp shows a hair-density gain over placebo injections in pooled trials, but the studies disagree with each other and are of low quality, so treat it as promising, not proven.

In detail

Platelet-rich plasma (PRP) is prepared by spinning down a sample of the patient's own blood and injecting the platelet concentrate into the scalp, on the idea that platelet growth factors stimulate follicles. The 2023 meta-analysis in Blood Transfusion found a statistically significant density advantage over saline (25.6 hairs per cm2) but graded the evidence low quality for inconsistency and bias, and protocols vary widely between clinics. It is not standardized, it is usually paid for out of pocket, and it requires repeated sessions.

How to use it

A reasonable add-on for someone already committed to standard treatment who accepts the cost and the uncertainty, not a replacement for minoxidil or finasteride, and worth asking a clinic how their protocol compares with the trials.

The study · 1

Cruciani et al., Platelet-rich plasma for the treatment of alopecia: a systematic review and meta-analysis · Blood Transfus 2023;21(1):24-36

Low-level laser therapy beats sham devices but on uneven evidenceEmerging

In plain terms

Laser caps and combs beat sham devices on hair count in pooled trials, but the studies are uneven and the devices are expensive. It is a possible add-on, not a substitute for the proven treatments.

In detail

Low-level laser therapy (LLLT, also called red-light or photobiomodulation devices) delivers red light to the scalp, and the 2017 meta-analysis found it superior to placebo alongside minoxidil and finasteride. A 2023 guidance review cautions that the evidence quality varies greatly and standardized protocols are missing. The devices are cleared for hair growth and are low-risk to use, but they are costly, require frequent regular use, and are less well supported than minoxidil or finasteride.

How to use it

Reasonable as an adjunct for someone who will use it consistently and can afford it, ideally on top of minoxidil, not instead of it. Judge any specific device against the thin, uneven evidence, not its marketing.

The studies · 2

Adil & Godwin, The effectiveness of treatments for androgenetic alopecia: a systematic review and meta-analysis · J Am Acad Dermatol 2017;77(1):136-141.e5

Kaiser et al., Treatment of Androgenetic Alopecia: Current Guidance and Unmet Needs · Clin Cosmet Investig Dermatol 2023;16:1387-1406

Counts once: this finding and 2 others here come from the same source, so they are one body of evidence, not separate confirmations.

Steroid injections for alopecia areata rest on weak trial evidencePreliminary · mixed

In plain terms

Steroid injections into the bald patches are the usual first treatment for a few patches of alopecia areata, and they often help in practice, but the controlled trial evidence behind them is surprisingly weak.

In detail

Intralesional corticosteroid injections have been the mainstay for limited alopecia areata for decades and are widely used because patches often regrow after them. The 2023 Cochrane meta-analysis, however, rated the head-to-head evidence against placebo as very uncertain, and found only low-certainty support for oral corticosteroids over short periods. Here standard practice is better established than the controlled-trial evidence. They are best suited to a small number of patches and are limited by injection discomfort and, with repeated use, local skin thinning.

How to use it

Reasonable for a few patches under a clinician, accepting that the benefit is supported more by long practice than by strong trials, and that extensive disease is where the JAK inhibitors have the stronger evidence.

The study · 1

Mateos-Haro et al., Treatments for alopecia areata: a network meta-analysis (Cochrane review) · Cochrane Database Syst Rev 2023;10(10):CD013719

Counts once: this finding and 1 other here come from the same source, so they are one body of evidence, not separate confirmations.

Caffeine shampoos and OTC topicals rest on about 11 small studiesPreliminary · mixed

In plain terms

Caffeine shampoos and the various natural or over-the-counter hair products rest mostly on laboratory work and a few small studies. The evidence is too thin to say they work.

In detail

Caffeine can stimulate hair follicles in laboratory dishes, which is where much of the marketing comes from, but the clinical evidence in people is sparse. A 2017 systematic review looked specifically at topical caffeine for male androgenetic alopecia, and a 2022 review of natural products found the whole category of caffeine, saw palmetto, rosemary oil, pumpkin seed oil, marine extracts and the like was supported by only around 11 clinical studies combined, leading the authors to the hedged conclusion that such products might be considered. That is a fair summary of the field: laboratory plausibility, a handful of small human studies, and no basis for choosing them over the proven treatments.

How to use it

Harmless to try if they are cheap and you enjoy them, but not a reason to delay minoxidil or finasteride, and not worth paying a premium for on the current evidence.

The studies · 2

Dressler et al., Efficacy of topical caffeine in male androgenetic alopecia (systematic review) · J Dtsch Dermatol Ges 2017;15(7):734-741

Gupta et al., Complementary and alternative treatments for alopecia: natural products for male androgenetic alopecia · Dermatol Ther 2022;35(4):e15323

Measurement And Diagnosis

L'effluvium télogène repousse de lui-même après que le déclencheur soit passéModerate

In plain terms

La chute diffuse importante qui suit une maladie, un accouchement ou un stress majeur est presque toujours un effluvium télogène, et les cheveux repoussent une fois le déclencheur passé. Cela semble alarmant et c'est l'un des rares types de perte de cheveux qui se résout d'elle-même.

In detail

Dans l'effluvium télogène, le cycle pilaire normal est perturbé : un choc physiologique fait passer simultanément de nombreux follicules de la phase de croissance (anagène) à la phase de repos (télogène), et ils tombent ensemble deux à trois mois plus tard, c'est pourquoi la cause est généralement quelque chose qui s'est produit des mois avant le début de la chute. La revue de 2014 décrit l'effluvium télogène aigu comme auto-limitant avec récupération une fois le déclencheur résolu, tandis qu'une forme chronique peut suivre un cours intermittent et récidivant. Le point clinique clé est qu'il amincit de manière diffuse, sans créer de plaques chauves, et ne cicatrise pas, de sorte que les follicules restent capables de repousser.

Who this may not transfer to:More often described in women, partly because pregnancy and heavier periods are common triggers, but it occurs in both sexes.

How to use it

Identifier et traiter le déclencheur, vérifier le fer et la thyroïde si la chute est importante ou lente à se stabiliser, et lui laisser le temps ; le traitement est la réassurance, pas des médicaments, sauf si cela se prolonge ou revient.

The study · 1

Rebora, Telogen effluvium revisited · G Ital Dermatol Venereol 2014;149(1):47-54

Un faible taux de fer peut entraîner une chute, et corriger une vraie carence aideEmerging

In plain terms

Un faible taux de fer peut entraîner une chute diffuse, surtout chez les femmes, alors faites une prise de sang si vous perdez vos cheveux. Corriger une carence confirmée peut aider, mais le fer ne fait rien pour les cheveux si vos réserves sont déjà normales.

In detail

Le fer est nécessaire aux cellules à division rapide du follicule pileux, et une faible ferritine a été associée à plusieurs reprises à l'effluvium télogène, avec des travaux transversaux corrélant la ferritine à cette condition. La revue de 2006 par Trost et ses collègues, encore un point de référence, a conclu que les preuves n'étaient pas suffisamment solides pour recommander un dépistage ou une supplémentation universelle sans anémie, tout en notant l'association dans plusieurs types de perte de cheveux et que de nombreux cliniciens effectuent quand même un dépistage. Il s'agit d'un tableau associationnel, pas d'une preuve par essai que les comprimés de fer font repousser les cheveux, donc la valeur réside dans la détection et la correction d'une véritable carence, pas dans la prise de fer par précaution.

Who this may not transfer to:The association is studied mainly in women, in whom iron deficiency is more common; it is less well characterized in men.

How to use it

Demander un test de ferritine en cas de chute diffuse, surtout avec des règles abondantes ou un régime limité, et prendre du fer uniquement s'il est faible, car le fer sans carence n'aide pas et peut causer des effets secondaires gastro-intestinaux.

The studies · 2

Trost et al., The diagnosis and treatment of iron deficiency and its potential relationship to hair loss · J Am Acad Dermatol 2006;54(5):824-844

İbiş et al., Evaluation of MCV/RDW ratio and correlations with ferritin in telogen effluvium patients · Dermatol Pract Concept 2022;12(3):e2022151

What the Marketing Gets Wrong

Hair loss is one of the most heavily marketed corners of health, and most of what is sold does less than the packaging suggests. Biotin is the clearest case. It helps hair only in the rare person with a true biotin deficiency. For anyone with normal levels, which is most people, it does nothing measurable. It also distorts some blood tests, including thyroid and cardiac ones, so mention it before bloods are drawn. Most multi-ingredient hair-growth vitamins sit in the same position.

Caffeine shampoos and the wider category of natural and over-the-counter topicals rest mostly on laboratory work and a few small studies, too thin to say they work. They are cheap and low-risk to try. But they are not a reason to delay minoxidil or finasteride, and not worth paying a premium for on the current evidence. Laser caps and combs do beat sham devices in pooled trials, but the studies are uneven and the devices are expensive. That keeps them an add-on.

Two more findings temper the standard advice. Finasteride, the mainstay for men, did not beat placebo in women with pattern loss, so minoxidil is the first-line drug for women. Finasteride is avoided in women who could become pregnant. The steroid injections used for a few patches of alopecia areata are standard practice for decades. They rest on surprisingly weak controlled-trial evidence, a case where practice is better established than the trials.

How It Works

Hair grows in a cycle. Most follicles are in a long growing phase, a small share are resting, and the resting ones shed as new hair pushes through. The different kinds of loss are different disturbances of that cycle.

In pattern loss, the androgen dihydrotestosterone (DHT) gradually miniaturizes genetically susceptible follicles, so each cycle produces a finer, shorter hair until the follicle stops. Finasteride and dutasteride block the enzyme that makes DHT; minoxidil lengthens the growing phase and widens the follicle. The two act by different routes, which is why they combine well.

In telogen effluvium a physiological shock pushes a large batch of follicles from the growing phase into the resting phase at once. They shed together two to three months later. That delay is why the cause is usually something that happened months before the shedding began. Nothing is destroyed, so the follicles re-enter growth and the hair returns.

Alopecia areata is autoimmune. The immune system attacks the follicle but leaves it intact, so it can regrow, and the JAK inhibitors work by interrupting that immune signal. The scarring alopecias are the exception. There the follicle itself is destroyed and replaced by scar tissue, so no treatment regrows hair from an area that has already scarred. The goal is to halt the inflammation and save the follicles that remain.

Go Deeper

• Iron: the ferritin blood test behind diffuse shedding, when a low store is worth correcting, and why iron does nothing for hair if your levels are normal.
• A whole-foods way of eating: why very low-calorie or low-protein eating can tip the hair cycle into shedding, and the pattern that supports normal growth.
• Copper peptides (GHK-Cu): the topical marketed for thinning hair, and how its small evidence compares with the treatments that actually work.

Cautions

Extra restraint

Everything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.

Finasteride raises the risk of sexual side effects about 1.57-fold

The 2019 meta-analysis by Lee and colleagues pooled 15 randomized trials of finasteride or dutasteride for male androgenetic alopecia and found the drugs increased sexual dysfunction overall by about 57% relative to control, driven by finasteride. Absolute rates in the trials were low, in the low single-digit percentages, and the great majority of affected men recovered after discontinuation. A contested minority report persistent symptoms after stopping, an area still debated and not resolved by this analysis.Lee et al., Adverse sexual effects of treatment with finasteride or dutasteride for male androgenetic alopecia: a systematic review and meta-analysis

L'alopécie cicatricielle est permanente sans traitement précoce

Les alopécies cicatricielles primaires sont un groupe de conditions inflammatoires dans lesquelles le follicule lui-même est la cible et est remplacé par du tissu cicatriciel, de sorte que les cheveux ne peuvent pas repousser dans ces zones. À l'examen, le cuir chevelu semble lisse et brillant et les ouvertures folliculaires sont perdues, parfois avec de la rougeur, une desquamation ou des pustules au bord de la zone active. Le diagnostic nécessite généralement une biopsie du cuir chevelu, et le traitement vise à stopper l'inflammation et à préserver les follicules restants, pas à récupérer ce qui a déjà cicatrisé. C'est pourquoi une plaque cicatricielle lisse, ou toute perte de cheveux avec rougeur, douleur ou pustules du cuir chevelu, justifie une évaluation spécialisée rapide.Goldberg et al., Alopecia: new building blocks (clinical review)Stefanato, Histopathology of alopecia: a clinicopathological approach to diagnosis

The anti-androgens are avoided in pregnancy

Finasteride and dutasteride can harm a developing male fetus, and spironolactone, sometimes used for female pattern loss, acts on the same hormonal pathway. All three are avoided in women who are or could become pregnant, so any anti-androgen for a woman is a decision made with a prescriber who can arrange reliable contraception.

Traction loss becomes permanent if the pulling continues

Thinning along the hairline and parts from tight braids, buns, weaves, and extensions is reversible when caught early and permanent once the follicle scars. Loosening or changing the styling early, before the loss becomes fixed, is what protects the hairline.

Oral minoxidil acts on the whole body

The low-dose minoxidil tablet is convenient, but because it is systemic it can cause unwanted body-hair growth, fluid retention, and, uncommonly, effects on the heart. It belongs with a prescriber who can screen for heart and blood-pressure issues and watch for side effects. It is not something to source and self-dose.

Most hair loss is common and either recovers on its own or responds to treatment that works better the earlier it starts. This is here to inform your choice, and a licensed clinician is the right person to weigh the prescription options with you.

When to See Someone

When to See Someone

Most hair loss is not dangerous, and much of it recovers or responds to treatment. These are the situations where seeing a professional is the right next step, some of them soon:

• A patch of scalp that has turned smooth, shiny, and slightly sunken, where the tiny openings the hairs grew from have disappeared, which can mean a scarring alopecia that destroys follicles for good and needs prompt dermatology before more follicles are lost(seek urgent care)
• Bald patches spreading quickly over days or weeks, or hair coming out in clumps, which needs assessment soon(seek urgent care)
• Hair loss alongside other symptoms such as marked tiredness, weight change, feeling the cold, a facial rash, or joint pains, which can point to a thyroid problem, iron deficiency, or an autoimmune condition
• Scalp redness, scaling, pain, itch, pustules, or a burning feeling with the loss, which points to an inflammatory or infective cause that has its own treatment
• Sudden heavy shedding that does not settle after a few months, or that keeps coming back, which is a reason to be seen
• Hair loss in a child, or loss of eyebrows, eyelashes, or body hair as well as scalp hair, which deserves a proper assessment
• Loss from long-standing tight braids, buns, weaves, or extensions, especially along the hairline, which can become permanent and is best caught early

None of this is meant to alarm you. Most hair loss is common, and either recovers on its own or responds to treatment that works better the earlier it starts. Knowing the few signs that need a closer look is part of dealing with it well.

Common Questions

Which hair-loss treatments actually work?

A short list does. For pattern loss, topical minoxidil is the proven first step for men and women, and for men, daily oral finasteride is the second mainstay, often used together. For widespread alopecia areata, oral JAK inhibitors regrow hair for a substantial share of people. Low-dose oral minoxidil, dutasteride, platelet-rich plasma, and laser caps are further options at varying strengths of evidence. Most of what else is sold, from biotin to caffeine shampoos, has little behind it.

Will my hair grow back?

It depends on the type. The heavy diffuse shedding that follows an illness, a birth, or major stress is almost always telogen effluvium. It grows back on its own over several months once the trigger has passed. Alopecia areata patches can also regrow, since the follicle is not destroyed. Pattern loss can be slowed and partly regrown with treatment, though not fully reversed, and it needs the treatment kept up. Scarring alopecia is the exception, because a scarred follicle cannot regrow, which is why catching it early matters.

Does biotin help hair?

Only if you are truly deficient in it, which is uncommon. The published basis for biotin and hair is a set of case reports in people who had an underlying deficiency. Nothing shows it helps hair in people whose levels are normal. It can also throw off certain lab results, thyroid and cardiac panels among them, so if you take it, tell any doctor ordering bloods. For most people it does nothing you can measure for hair.

Do caffeine shampoos and hair vitamins work?

The evidence is too thin to say they do. Caffeine can stimulate follicles in a laboratory dish, which is where much of the marketing comes from. But the studies in people are sparse, and the broader group of natural and over-the-counter hair products rests on a small handful of trials. They cost little and carry little risk, but they are no reason to delay the proven treatments, and not something to pay a premium for.

Is finasteride safe?

For most men it is well tolerated, and it is one of the two proven treatments for male pattern loss. A minority notice reduced libido or erectile problems, and that raised risk is worth discussing with a prescriber before starting. In the trials the absolute rates were low and most affected men recovered after stopping, while a contested minority report symptoms that persist. Finasteride is also kept away from women who could become pregnant.

When should I see a doctor about hair loss?

Soon if a patch of scalp has gone smooth and shiny with the pore openings lost. Also soon if patches are spreading fast or hair is coming out in clumps, or if there is scalp redness, scaling, pain, or pustules. Also worth a visit is shedding alongside tiredness, weight change, or feeling the cold, which can point to a thyroid or iron problem. So is any sudden heavy shedding that does not settle after a few months. The one where speed changes the outcome is scarring alopecia, so a smooth, shiny patch where the pores have vanished belongs with a dermatologist without delay.