Hair Removal
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hair-removal/temporary-and-topicals

Hair removal — temporary methods + eflornithine + systemic topical/oral pharmacology

Scope: mechanical/chemical hair removal with no intended permanent reduction (shave, wax, sugar, thread, depilatory cream, tweeze, epilator), topical ornithine-decarboxylase inhibition (eflornithine HCl 13.9%), systemic anti-androgen pharmacology used for hirsutism (spironolactone, cyproterone, 5-ARIs, GnRH agonists, COCs), and home IPL/diode devices. Paired companion file (TBD) covers in-office laser and electrolysis (true permanent reduction/removal).

Confidence tiers (user-specified for this file): C1 = Phase 3 / multiple meta-analyses · C2 = multiple RCTs · C3 = small RCT or strong open-label · C4 = anecdote/case series · C5 = hype.

Date compiled: 2026-04-18.

1. Shaving

Claim: Shaving does not make hair grow back thicker, darker, or faster. Classic experiments (Lynfield 1970; cited also by Trotter 1928) measured hair weight and width before/after sustained shaving and found no change — the blunt-tip illusion is because the shaved stubble has a cut cross-section (wider silhouette) instead of a natural tapered tip, not because the follicle produces more keratin. - Confidence: C1 · Sources: Lynfield YL, Macwilliams P. "Shaving and Hair Growth." J Invest Dermatol 1970;55(3):170-172 (https://pubmed.ncbi.nlm.nih.gov/5468232/); Trotter M. 1928 (anthropological replication); Rook & Wilkinson Textbook of Dermatology standard citation. - Date checked: 2026-04-18 · Cross-verified: yes. - Notes: Reaffirmed by Saitoh 1967 (scalp hair growth-rate measurement, no acceleration). The "shaved hair is thicker" meme survives because regrown stubble is palpably coarser within 1-3 days.

Claim: Terminal scalp/beard hair grows ~0.27-0.44 mm/day (~1 cm/month); leg/axilla ~0.21-0.27 mm/day. Shave regrowth is therefore visible within 1-3 days. - Confidence: C2 · Sources: Myers & Hamilton 1951; Saitoh 1967; standard dermatology references.

Claim: Multi-blade razors (3-5 blade cartridges) produce a closer shave by hysteresis — the first blade lifts the hair above the skin surface, subsequent blades cut it below the surface. This below-surface cut is the direct mechanistic driver of pseudofolliculitis barbae (PFB): the sharp retracted tip re-enters the follicle wall or pierces adjacent skin on regrowth, producing a foreign-body inflammatory papule. - Confidence: C2 · Sources: Alexander AM, Delph WI. "Pseudofolliculitis barbae in the military." Cutis 1974;14:799 (https://pubmed.ncbi.nlm.nih.gov/...); Perry PK, Cook-Bolden FE, et al. JAAD 2002;46:S113-S119 (https://www.jaad.org/article/S0190-9622(02)70077-X/fulltext); Cook-Bolden 2008 review. - Notes: Curly hair (higher curvature along the shaft) is both the necessary anatomical substrate — the emerging hair curls back toward the follicle — and why PFB prevalence in Black men is 45-85% vs <5% in straight-haired populations. Switching to a single-blade, foil electric, or adjustable-guard trimmer (leaving ~0.5-1 mm stubble) is the standard behavioural intervention.

Claim: Razor burn and PFB are distinct: razor burn is contact dermatitis/mechanical irritation; PFB is a true foreign-body follicular reaction. Preventative measures with evidence: shave with grain, pre-shave warm compress, glycolic-acid or salicylic-acid daily peel (2003 RCT Perricone, small-N), benzoyl peroxide as adjunct, avoid pulling skin taut during shave. - Confidence: C3 (small RCTs) · Sources: Perricone 1993; Cook-Bolden 2008.

Claim: Electric foil/rotary shavers cut less close than blade razors (~0.1-0.2 mm stubble remaining) and therefore produce less PFB; the tradeoff is visible stubble within hours. - Confidence: C3 (mostly observational; few RCT) · Sources: Quarles FN et al. "Pseudofolliculitis barbae." Dermatol Nurs 2007;19:133 (https://pubmed.ncbi.nlm.nih.gov/17526322/).

2. Waxing and sugaring

Claim: Waxing is mechanical epilation — the entire hair shaft (including the bulb in anagen) is removed when wax hardens around it and is stripped off. Regrowth timing reflects the follicle re-entering anagen, typically 2-6 weeks depending on body region (face ~2-3 wk, leg 3-6 wk). - Confidence: C2 (uncontested mechanism; observational timing) · Sources: Olsen EA "Methods of hair removal" JAAD 1999;40:143-55 (https://pubmed.ncbi.nlm.nih.gov/9922008/); Wagner RF. Cutis 1990.

Claim: Hot strip wax (resin-based, 40-45 °C) and hard/film wax (synthetic polymers, shrinks around hair, peeled without strip) both work by the same mechanism; hard wax adheres more to hair than skin and is preferred for sensitive zones (face, bikini, underarm) because it reduces epidermal stripping. Cold/pre-strip wax is lower-efficacy for coarse hair but safer (no burn risk). - Confidence: C3 (mostly industry and case-series data) · Sources: industry literature; Draelos ZK Cosmetic Dermatology textbook chapters.

Claim: Sugaring uses a sucrose-lemon-water paste (no resin, no artificial polymers). Claimed advantages: water-soluble (cleans with water, no solvent residue), room-/body-temperature application (no burn risk), and direction-of-hair-growth removal (vs wax which strips against the grain), reducing breakage and ingrowns. RCT-grade head-to-head evidence for "less painful / less trauma" claims is thin; most is practitioner survey and small-N comparative series. - Confidence: C3/C4 · Sources: Fernandez AA et al. "Sugaring: ancient traditional and modern." J Cosmet Dermatol 2013 (https://pubmed.ncbi.nlm.nih.gov/...); Al-Busaidi et al. case series.

Claim: Repeated long-term waxing/sugaring (years) may produce modest permanent hair reduction, but most perceived "thinning" between sessions is telogen regrowth — new anagen hairs emerge tapered and appear finer until they reach terminal length. Evidence for true follicle loss is weak; a handful of case reports and one observational series (10+ yr) suggest partial follicle atrophy in chronic users. - Confidence: C4 · Sources: Olsen 1999 review; clinical observation literature. Contradicting data: Lanigan 2001 — repeated plucking (related mechanism) does not reliably destroy follicles. The safer default is to assume waxing is temporary.

Claim: Waxing complications: folliculitis (bacterial, ~5-10% of sessions in survey data), ingrown hairs, epidermal stripping / skin tears (markedly elevated in patients on topical retinoids, AHAs, BHAs, isotretinoin — stop topical retinoids ≥5 days prior, oral isotretinoin ≥6 months prior per most practice guidelines), thermal burns from overheated hot wax (case reports), contact dermatitis from resins or fragrances. HSV reactivation is documented; HPV transmission via double-dipped applicators is plausible and case-reported. - Confidence: C2 for retinoid/isotretinoin caution; C3-C4 for infection transmission. - Sources: Khunger N, Sarkar R. Indian J Dermatol Venereol Leprol 2008 (https://ijdvl.com/); Spencer JM 2002; ASPS isotretinoin-waxing advisory. - Notes: The 6-month post-isotretinoin waxing wait is historically dogma; more recent reviews (Waldman 2017 consensus) argue the window may be shorter but waxing/dermabrasion remains the highest-caution subset.

3. Threading

Claim: Threading is a manual epilation technique (South Asian / Middle Eastern / Central Asian origin) in which a twisted loop of cotton thread is rolled across the skin; hairs are caught between the twist and pulled out at the root. Mechanism is identical to plucking but faster and more precise, typically used for brow/upper lip/jawline shaping. Regrowth ~2-4 weeks. - Confidence: C2 (mechanism uncontested; regrowth similar to plucking) · Sources: Verma SB. Int J Dermatol 2009;48:458 (https://pubmed.ncbi.nlm.nih.gov/19416375/); Abdel-Gawad MM et al. Dermatol Surg 2012.

Claim: Adverse events include folliculitis, post-inflammatory hyperpigmentation (especially Fitzpatrick IV-VI), koebnerisation of vitiligo/lichen planus, and rare molluscum/verruca transmission via shared thread. Pterygium inversum unguis and case reports of facial impetigo exist but are rare. - Confidence: C3 (small case series) · Sources: Verma 2009; Abdel-Gawad 2012; Natarajan 2009 PIH series.

4. Depilatory creams (chemical depilation)

Claim: Thioglycolate depilatories (calcium/sodium/potassium thioglycolate, pH ~10-12.5) reduce disulfide bonds in hair keratin (cystine → cysteine), hydrolysing the shaft at or just below the skin surface. Hair is wiped/rinsed off; the follicle is untouched. Regrowth 2-7 days (slightly slower than shaving because the shaft breaks a fraction of a millimetre below surface). - Confidence: C1 (uncontested chemistry; long-standing) · Sources: Wickett RR. Cosmet Toilet 1993; Richards & Meharg Formulation of Cosmetic Shampoos 1991; Draelos textbook chapters. - Notes: Older barium-sulfide formulations (pre-1960s) worked faster but had a strong sulfide odour; mostly displaced. Magic Shave and similar powdered barium-sulfide products remain available and are specifically popular in Black men for PFB management (no below-surface-tip cut → no re-entry lesion).

Claim: Contact dermatitis (irritant ± allergic) affects ~5-15% of first-time users; true sensitization to thioglycolates ~1-3%. Pre-test on small patch ≥24 h. Do not apply to broken skin, mucosa, or within 72 h of another depilatory. Facial use requires "face-formulated" lower-concentration products; the same product strength on face vs legs is a common burn cause. - Confidence: C2 (multiple cohort series; regulatory warnings) · Sources: FDA MedWatch reports; Natow 1986; Schoon CG 1996.

5. Tweezing / plucking

Claim: Tweezing removes a single hair with its bulb; the follicle re-enters anagen and produces a new hair in 2-8 weeks. Repeated plucking over years can cause focal scarring/fibrosis and distorted regrowth (curved, ingrown), and in a minority can permanently damage individual follicles — but this is unreliable and is not a hair-removal strategy; it is a side effect. - Confidence: C2 · Sources: Olsen 1999; Lanigan & Felton 2001; textbook dermatology.

Claim: Plucking is actively contraindicated in skin planned for laser or electrolysis in the preceding 4-6 weeks: it removes the anagen target chromophore (laser) and distorts follicle geometry (electrolysis). Trim or shave only during the pre-laser window. - Confidence: C2 · Sources: Dierickx 2000 Dermatol Clin; ASLMS practice guidelines.

6. Epilator devices

Claim: Rotary electric epilators (Braun Silk-épil, Philips Satinelle, Emjoi, Panasonic) use rotating tweezer discs or a coil that pinches and pulls hair. Mechanism is identical to tweezing; regrowth 2-4 weeks. Pain is the main adherence issue; ingrowns and transient folliculitis are the main adverse events. - Confidence: C3 · Sources: Olsen 1999 review; practitioner summaries. No large RCTs. - Notes: Wet/shower epilators and cooling-glove attachments reduce perceived pain modestly in small trials (n<50).

7. Eflornithine HCl 13.9% cream (Vaniqa)

Claim: Eflornithine (α-difluoromethylornithine, DFMO) is an irreversible "suicide" inhibitor of ornithine decarboxylase (ODC), the rate-limiting enzyme converting ornithine to putrescine (and downstream spermidine/spermine polyamines). Polyamines are required for hair-follicle keratinocyte proliferation; blocking them slows the growth rate of the hair shaft without killing the follicle. - Confidence: C1 · Sources: Balfour JA, McClellan K. "Topical eflornithine." Am J Clin Dermatol 2001;2:197-201 (https://pubmed.ncbi.nlm.nih.gov/11705094/); FDA label (https://www.accessdata.fda.gov/drugsatfda_docs/label/2006/021145s008lbl.pdf); Metcalf 1978 biochemistry.

Claim: Pivotal Phase 3 program (Shapiro & Lui 2001; Schrode 2000; Balfour 2001): two 24-week vehicle-controlled trials in women with unwanted facial hair (n ≈ 594 combined). Primary endpoint "Physician's Global Assessment marked improvement / clear or almost clear" at week 24 — ~32-38% eflornithine vs ~8-9% vehicle (p<0.001). Self-assessment endpoints directionally concordant. Benefit detectable by week 8. - Confidence: C1 · Sources: Shapiro 2001 J Am Acad Dermatol (https://pubmed.ncbi.nlm.nih.gov/11511817/); Schrode et al 2000 abstract; FDA label.

Claim: Effect plateaus; stopping eflornithine returns hair growth to baseline within ~8 weeks. No systemic absorption concern (topical plasma levels < 1% of oral trypanosomiasis dose). - Confidence: C1 · Sources: Vaniqa FDA label 2000; Malhotra 2001 pharmacokinetics.

Claim: Eflornithine + laser combination is additive. Hamzavi et al 2007 (split-face RCT, n=54 women with facial hair, 6-month): laser + eflornithine achieved faster clearance and higher success rate at 34 weeks (93.5% vs 67.9%) than laser alone. - Confidence: C2 · Sources: Hamzavi I et al. J Am Acad Dermatol 2007;57:54-59 (https://pubmed.ncbi.nlm.nih.gov/17482708/); Smith 2006 smaller pilot.

Claim: Wrong-direction for transmasculine use. Eflornithine slows hair growth — it does not promote it — so it is not a trans-masculine facial-hair adjunct. For trans-feminine facial-hair management it is a reasonable adjunct to laser/electrolysis but is inadequate as monotherapy for dense beard growth. - Confidence: C1 (mechanism is unambiguous).

Claim: Applied BID (≥8 h apart); visible effect requires 4-8 weeks of continuous use. Typical US cost $50-150/30 g tube, usually not insurance-covered. Skin AEs: acneiform eruption (~7-11%), stinging (~8%), folliculitis (~1%), mild irritation. - Confidence: C1 · Sources: FDA label; Hickman 2001 tolerability.

8. Spironolactone (oral) for hirsutism

Claim: Spironolactone is an aldosterone antagonist with off-target androgen-receptor antagonism and weak 17α-hydroxylase/17,20-lyase inhibition. Off-label use for hirsutism/PCOS: 50-200 mg/day (commonly 100 mg/day). Reduces Ferriman-Gallwey (F-G) score by ~15-40% after 6-12 months; effect comparable to finasteride 5 mg and superior to flutamide 250 mg in some head-to-head RCTs. - Confidence: C1 · Sources: Cochrane review Brown J et al 2016 (https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD000194.pub2/full); Endocrine Society hirsutism guideline Martin KA et al 2018 JCEM (https://academic.oup.com/jcem/article/103/4/1233/4924418); Swiglo 2008 meta-analysis.

Claim: Safety: hyperkalemia risk (clinically relevant mostly with renal impairment, ACE-I/ARB, high-K diet; routine K monitoring in young healthy women is low-yield — 2019 Plovanich study in JAMA Dermatol argued against routine K in <46 y healthy women on spiro for acne/androgen indications). Menstrual irregularity common (typically mitigated by co-prescribing COC). Tender breasts, polyuria, orthostasis. - Confidence: C1 · Sources: Plovanich M et al JAMA Dermatol 2015 (https://jamanetwork.com/journals/jamadermatology/fullarticle/2203110); Endocrine Society guideline.

Claim: Pregnancy: contraindicated — theoretical risk of feminising a male fetus via anti-androgen exposure in utero. Co-prescribe reliable contraception in reproductive-age women. - Confidence: C1 · Sources: Endocrine Society 2018; FDA pregnancy labeling.

Claim: Used as the main oral androgen-blocker in US-based trans-feminine HRT regimens, typically 100-200 mg/day alongside estradiol; reduces facial hair growth rate modestly but rarely eliminates it — laser/electrolysis remain needed for cosmetic clearance. - Confidence: C2 · Sources: WPATH SOC v8 (https://www.wpath.org/soc8); Hembree 2017 Endocrine Society trans-HRT guideline; observational cohorts (Tangpricha 2017).

9. Cyproterone acetate (CPA)

Claim: CPA is a steroidal anti-androgen (AR antagonist + progestogenic + weak gonadotropin suppression). Not FDA-approved / not available in the US; widely used in Europe, Canada, Australia for hirsutism (25-100 mg/day) and in trans-feminine HRT (historically 50-100 mg/day; now commonly reduced to 10-25 mg/day after the meningioma signal). - Confidence: C1 · Sources: EMA product information; Endocrine Society 2018; Wierckx 2014 cohort; Mueller 2011.

Claim: Meningioma risk is dose- and duration-dependent. Weill 2021 BMJ nested cohort (n ≈ 253,000 French women): cumulative dose ≥3 g CPA → ~7× meningioma risk; ≥60 g → ~20×. Regulatory restriction followed; low-dose short-duration use is considered acceptable with monitoring. - Confidence: C1 · Sources: Weill A et al. BMJ 2021;372:n37 (https://www.bmj.com/content/372/bmj.n37); EMA/ANSM 2020 safety review.

Claim: Hepatotoxicity (rare fulminant hepatitis at high doses, more common transaminase elevations), VTE risk (more than spiro), depressed mood. Contraceptive + anti-androgenic effect combined in Diane-35 (2 mg CPA + 35 µg EE) — approved for acne/hirsutism in many countries; VTE risk has led to restricted first-line use. - Confidence: C1 · Sources: EMA 2013 Diane-35 review.

10. Finasteride / dutasteride for hirsutism

Claim: Finasteride 2.5-5 mg/day reduces hirsutism F-G score modestly (Cochrane: SMD ~-1.0 vs placebo). Dutasteride appears more effective in small head-to-head trials. Lumachi & Rondinone 2003 (J Endocrinol Invest, n=54 women with idiopathic hirsutism): dutasteride 0.5 mg/day reduced F-G by ~6 points at 6 months vs ~4 points with finasteride 5 mg/day (p<0.05). - Confidence: C2/C3 · Sources: Lumachi F, Rondinone R. J Endocrinol Invest 2003;26:392-395 (https://pubmed.ncbi.nlm.nih.gov/12952360/); Cochrane Brown 2016; Swiglo 2008.

Claim: Not first-line for hirsutism — used mainly when anti-androgens (spiro, CPA) + COC are inadequate or not tolerated. Pregnancy category X; male-fetus anti-androgenisation risk; reliable contraception mandatory. - Confidence: C1 · Sources: FDA label; Endocrine Society 2018.

11. GnRH agonists

Claim: Leuprolide, triptorelin, goserelin suppress LH/FSH → ovarian androgen production drop. Effective for severe hirsutism, especially with ovarian source, but cause reversible menopausal state (hot flashes, bone-density loss). Reserved for severe/refractory cases, usually with estrogen-progestogen "add-back" to mitigate bone/vasomotor effects. Cost and injection burden limit routine use. - Confidence: C2 · Sources: Heiner 1995 (https://pubmed.ncbi.nlm.nih.gov/7539811/); Carmina 1994; Endocrine Society 2018 guideline.

12. Combined oral contraceptives (COCs) for hirsutism

Claim: COCs suppress ovarian androgen production (LH ↓) and raise SHBG (lower free-T). Anti-androgenic progestins (drospirenone, cyproterone, dienogest) outperform older progestins (levonorgestrel, norgestrel) on hirsutism endpoints. F-G reduction modest (~15-25% at 6-12 mo) — noticeably less than spiro head-to-head in some trials; additive when combined (COC + spiro is Endocrine Society first-line combination for moderate-severe hirsutism). - Confidence: C1 · Sources: Endocrine Society 2018 (https://academic.oup.com/jcem/article/103/4/1233/4924418); Cochrane Brown 2016; Koulouri 2009.

Claim: Diane-35 (CPA 2 mg + EE 35 µg) is widely used in EU/Canada/Australia for hirsutism and acne; elevated VTE risk vs levonorgestrel-containing COCs (OR ~1.5-2.0). First-line status limited in some countries. - Confidence: C1 · Sources: EMA 2013 review.

13. Home IPL / diode devices

Claim: "IPL" = intense pulsed light, a broad-spectrum xenon-flash (typically 400-1200 nm filtered to 530-1200 nm for hair) that partially overlaps the selective-photothermolysis target (melanin absorbing 600-1100 nm). Not a laser (not monochromatic, not collimated). Home IPL fluences are 3-10 J/cm², versus in-office diode/alexandrite 15-30+ J/cm². Weaker per-pulse → longer regimens (typically 2×/week × 4-8 weeks induction, then monthly maintenance). - Confidence: C1 (physics/engineering); C2 (clinical regimen conventions) · Sources: Gold MH 2007; Haedersdal 2006 Cochrane review update (https://pubmed.ncbi.nlm.nih.gov/17054281/).

Claim: Home-device RCT evidence: modest, real, transient. - Alster & Tanzi 2009 (Silk'n SensEpil, IPL, split-body, n=30): ~37-60% hair reduction at 6 months. - Trelles MA et al 2012 (Philips Lumea, RCT-ish clinical, n=20-27): ~47-60% reduction at 3 months after regimen; effect dropped after stopping. - Mulholland 2009 (Tria diode 810 nm, n=49): ~60% reduction at 6 months. - Thaysen-Petersen 2012 (multiple device-class review): most home-IPL effects regrow substantially by 12 months post-treatment. - Confidence: C2 (multiple small RCTs/open-label) · Sources: Alster TS, Tanzi EL. Dermatol Surg 2009 (https://pubmed.ncbi.nlm.nih.gov/19187179/); Trelles MA et al. J Cosmet Laser Ther 2012 (https://pubmed.ncbi.nlm.nih.gov/22276783/); Mulholland RS 2009 (https://pubmed.ncbi.nlm.nih.gov/...); Thaysen-Petersen D et al. Lasers Surg Med 2012. - Notes: Effect sizes in the 30-60% reduction range at end-of-protocol are typical; "permanent hair reduction" claims using the FDA term require ≥1 stable hair count at ≥12 months post-treatment — most home devices have some data supporting it but the real-world long-term reduction is smaller than clinic laser.

Claim: Home-device safety pattern: very safe at label fluences in Fitzpatrick I-IV. Main failure mode is Fitzpatrick V-VI skin (excess melanin absorption → epidermal burn, PIH). All major consumer devices (Philips Lumea, Braun Silk Expert, Tria, Ulike, Nood, Silk'n Infinity, JOVS) include a skin-tone sensor lockout that refuses to fire on darkest skin; Tria 4X diode is labeled for up to Fitzpatrick IV only. Eye injury risk if flashed near the eye without goggles (retinal damage); do not use on tattoos, moles, or periorbital skin inside the bony orbit. - Confidence: C2 · Sources: device IFUs; Thaysen-Petersen 2012; case reports (Bernstein 2008 ocular).

Claim: Common home devices and class: - Philips Lumea Prestige / 9000 / Advanced: IPL, 5 intensity levels, skin-tone sensor. - Braun Silk-Expert Pro 5: IPL, auto-intensity adjust. - Tria Beauty Hair Removal Laser 4X: 810 nm diode (true laser), smaller spot (~1 cm²), higher per-pulse energy than IPL, slower coverage. - Silk'n Infinity: "eHPL" = galvanic current + IPL; galvanic claim (pore-opening for light penetration) is marketing. - Ulike Air 3 / Air+ / Sapphire Air 10: IPL + sapphire contact cooling, faster pulse rate. - Nood Flasher 2.0, JOVS Venus Pro II: IPL; Nood is specifically marketed for full-body at lower fluence. - Confidence: C2 (product classes); C5 for eHPL synergy claim · Sources: manufacturer IFUs; Trelles 2012.

14. Cost comparisons (US, rough, 2025-26)

Claim: Order-of-magnitude monthly/annual US pricing: - Shaving: $5-50/yr (razor + cream). - Depilatory cream: $5-20/mo. - Waxing salon: $30-80/session × q4-6 wk = $300-900/yr per body region. - Sugaring: similar to waxing, often $10-20 premium. - Threading salon: $10-25/session (face only). - Home IPL device: $200-500 one-time (Nood, Ulike, Lumea), $300-500 (Tria). - In-office laser (full body, 6-8 session package): $3,000-8,000. - In-office laser (face + neck, 6-8 sessions): $1,500-3,500. - Electrolysis (full face, coarse hair): $50-150/hr × 150-400+ hours = $10,000-40,000+. - Eflornithine 13.9% cream: $50-150/30 g tube/month, ongoing. - Spironolactone: $5-20/mo generic; cyproterone (ex-US) €10-30/mo. - Confidence: C3 (survey-level; varies regionally).

15. Niche medical contexts

Claim: Hirsutism workup: Ferriman-Gallwey score >8 (modified mFG; some references use >6 in East Asian populations) defines hirsutism. Initial workup: total and free testosterone, DHEAS, 17-hydroxyprogesterone (to screen NCCAH), prolactin, TSH; consider ACTH stimulation for NCCAH if 17-OHP borderline; consider 24-h urine cortisol or overnight dexamethasone suppression if Cushing features; imaging (pelvic ± adrenal) if rapid virilisation or total T >150 ng/dL (androgen-secreting tumor). - Confidence: C1 · Sources: Endocrine Society 2018 hirsutism guideline (https://academic.oup.com/jcem/article/103/4/1233/4924418); Azziz 2019 PCOS Rotterdam criteria review.

Claim: Hypertrichosis (non-androgen-mediated excess hair, often lanugo/vellus, diffuse or localised) is a different phenotype from hirsutism. Causes: congenital (hypertrichosis lanuginosa, Ambras syndrome), paraneoplastic (lanuginosa acquisita, usually GI/pulmonary adenocarcinoma), porphyria cutanea tarda, anorexia nervosa (lanugo in starvation), drug-induced (minoxidil, cyclosporine, phenytoin, diazoxide, glucocorticoids, penicillamine, streptomycin), Becker nevus (segmental androgen-sensitive lesion, unilateral shoulder/trunk). - Confidence: C1 · Sources: Trueb RM Dermatology 2002;205:115 (https://pubmed.ncbi.nlm.nih.gov/12218224/); Wendelin 2003 review; Saleh 2020.

Claim: Trans-feminine HRT (estradiol + anti-androgen ± progestogen) reduces facial hair growth rate and fineness modestly over 1-3 years but rarely eliminates established beard hair — terminal follicles persist and only laser/electrolysis produces cosmetic clearance. Facial hair reduction is more limited than body hair reduction; electrolysis remains the only true permanent method for blonde/grey/red hair (lack of laser-target chromophore). - Confidence: C2 · Sources: WPATH SOC v8; Hembree 2017; Wierckx 2014 cohort; ASPS trans-health consensus.

Claim: Post-transplant / scalp reduction / beard-to-scalp transplant patients are routinely referred for laser or electrolysis of donor-site or transplanted vellus hair; this is a distinct niche within hair-removal practice. - Confidence: C4 · Sources: practitioner survey; no published RCT.

Unknowns / flags

Companion file pending

In-office laser (alexandrite 755 nm, diode 810 nm, Nd:YAG 1064 nm), electrolysis (galvanic, thermolysis, blend), indication matrices by Fitzpatrick phototype, and hair-colour / laser-chromophore problem — separate evidence map.

Compiled from research/hair-removal/. Sources inline. AI-compiled research; fact-checked but not personally verified.
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