Hirsutism

Hirsutism is excessive terminal (coarse, pigmented) hair growth in women, appearing in a male pattern — concentrated in androgen-dependent "sexual hair" areas such as the upper lip, chin, chest, abdomen, and back — and driven by androgen excess and/or an increased sensitivity of the hair follicle itself to circulating androgen.^[1] It must be distinguished from hypertrichosis: generalized excessive hair growth in a non-male, non-sexual-hair distribution (classically the forearms and lower legs), which is not androgen-driven — it is typically hereditary or medication-related (for example, phenytoin or cyclosporine) — although coexisting hyperandrogenemia can aggravate it.^[1] This distinction matters clinically: hypertrichosis does not warrant an androgen work-up, while hirsutism does.

Polycystic ovary syndrome (PCOS) is the single most common cause of hirsutism, accounting for 70-80% of cases,^[1] and many patients who present specifically for unwanted hair growth turn out to have a new PCOS diagnosis. This platform's dedicated Polycystic Ovary Syndrome chapter covers the Rotterdam diagnostic criteria, phenotypes, and full PCOS management approach in depth and is not repeated here. This chapter instead gives hirsutism itself — as its own presenting complaint — the diagnostic and pharmacotherapy depth it deserves: the full differential beyond PCOS (idiopathic hirsutism, nonclassic congenital adrenal hyperplasia, androgen-secreting tumours, and medication-induced hirsutism), the Ferriman-Gallwey scoring system used to quantify severity, and detailed anti-androgen and cosmetic pharmacotherapy. A substantial share of patients present for hirsutism specifically, not for a PCOS diagnosis — and every workup and treatment principle covered here applies equally when the underlying cause does turn out to be PCOS.

This chapter is authored primarily from the 2018 Endocrine Society Clinical Practice Guideline on the Evaluation and Treatment of Hirsutism in Premenopausal Women — the same authoritative source this platform's PCOS chapter already cites for its own anti-androgen guidance — cross-checked against the Society of Obstetricians and Gynaecologists of Canada's current Guideline No. 444 on hirsutism evaluation and treatment (2023), which independently confirms the same three-pronged management framework used throughout this chapter: mechanical hair removal, suppression of androgen production, and androgen-receptor blockade.^[2]

Quantifying severity — the modified Ferriman-Gallwey score

The modified Ferriman-Gallwey (mFG) score is the standard clinical tool for quantifying hirsutism severity and is considered the gold standard for this purpose.^[1] A trained examiner visually scores terminal hair growth at 9 body areas most sensitive to androgen — upper lip, chin, chest, upper back, lower back, upper abdomen, lower abdomen, arms, and thighs — each on a 0 (no terminal hair) to 4 (extensive, frankly male-pattern growth) scale; the forearms and lower legs are deliberately excluded from the modified version because hair growth at these sites does not correlate with androgen excess.^[1] The 9 individual scores are summed for a total ranging from 0 to 36.

A total score of 8 or more is the threshold most widely used to define hirsutism in white and Black women in the United States and United Kingdom, though the normal range varies meaningfully by ethnicity — the threshold runs higher in women of Mediterranean, Hispanic, or Middle Eastern background (≥9-10) and lower in South American (≥6) and some Asian populations (as low as ≥2 in Han Chinese women) — so interpret the score in the context of the patient's own background rather than a single fixed cutoff.^[1] The score has real limitations: it is subjective, does not capture a locally high score in a single sensitive area (for example, isolated chin or upper-lip growth) that never raises the total above the threshold, and does not include the sideburn area — use clinical judgement, not the number alone, particularly when a patient reports the hair growth as personally distressing regardless of the numeric score. This platform uses the term patient-important hirsutism for any degree of unwanted hair growth that causes sufficient distress for a patient to want treatment, which does not always track the mFG score closely.^[1]

The modified Ferriman-Gallwey chart — each of the 9 androgen-sensitive body areas is scored 0 (no terminal hair) to 4 (frankly male-pattern growth); the 9 area scores are summed for a total hirsutism score. (Kopera D, Wehr E, Obermayer-Pietsch B, CC BY 2.5, Wikimedia Commons)

Etiology — the differential beyond PCOS

The majority of hirsutism is due to androgen excess, and PCOS accounts for 70-80% of these cases^[1] — see the dedicated PCOS chapter for its Rotterdam-criteria diagnosis and full management. The remaining causes are where a dedicated hirsutism work-up earns its keep:

• Idiopathic hirsutism — hirsutism in a eumenorrheic (regularly cycling) woman with normal circulating total and free testosterone and no other clinical evidence of a hyperandrogenic endocrine disorder. This is a genuinely common finding: it accounts for roughly 5-20% of hirsute women overall, and for about half of women presenting with mild hirsutism specifically.^[1] The mechanism is thought to lie within the hair follicle itself rather than in the circulating hormone level — increased local 5α-reductase activity and/or androgen-receptor sensitivity in the pilosebaceous unit (sometimes termed "cutaneous hyperandrogenism") — which is why testosterone can be entirely normal despite clinically obvious hirsutism.^[1] Idiopathic hirsutism is a diagnosis of exclusion, made only once PCOS, nonclassic congenital adrenal hyperplasia, and other hyperandrogenic disorders have been reasonably excluded.
• Nonclassic congenital adrenal hyperplasia (NCCAH) — a partial, later-onset form of 21-hydroxylase deficiency, and an important and sometimes underdiagnosed differential, since its presentation (hirsutism, irregular menses, acne) can look identical to PCOS on the surface. Worldwide prevalence among hyperandrogenic women is about 4.2%, but this varies substantially by ancestry — roughly 1-2% in white and Hispanic women in the United States, 3-6% in women of Spanish, French, Italian, or Canadian background, 5-10% in Middle Eastern populations, and dramatically higher — up to a 37-fold increase — in Ashkenazi Jewish women.^[1] A positive family history or membership in a higher-risk ethnic group should lower the threshold to screen even when testosterone is normal (see Investigations).
• Androgen-secreting tumors of the ovary or adrenal gland are the critical red-flag category: rare (roughly 0.2% of hyperandrogenic women), but over half are malignant, so missing one has real consequences.^[1] These are distinguished clinically by a rapid pace of onset or progression (developing over months, not years), progression despite adequate therapy, and frank virilization — signs that go beyond hirsutism itself, including clitoromegaly, deepening of the voice, temporal balding, and a marked increase in muscle mass — together with markedly elevated androgen levels. See Red Flags & Referral.
• Other hyperandrogenic endocrinopathies — Cushing syndrome, acromegaly, and, rarely, hyperprolactinemia can all cause hirsutism, but patients with these conditions typically have other specific features (for example, proximal muscle weakness, wide violaceous striae, and easy bruising for Cushing syndrome) that point toward the diagnosis rather than presenting with hirsutism in isolation.^[1]

Medication-induced hirsutism

A careful medication history is a genuinely pharmacist-relevant step in every hirsutism work-up, since standard androgen assays do not detect exogenous androgenic drugs.^[1] Danazol, an attenuated (weakly androgenic) synthetic steroid used for endometriosis and, notably, for long-term prophylaxis of hereditary angioedema, is a well-documented cause — in one cohort of women using danazol and other attenuated androgens for hereditary angioedema, hirsutism was the single most commonly reported virilizing effect, reported by 42% of respondents.^[3] Anabolic-androgenic steroid use is another direct cause. Some progestins carry meaningfully higher intrinsic androgenicity than others (for example, levonorgestrel and norethindrone, relative to newer progestins such as norgestimate, desogestrel, or gestodene), which is one reason progestin choice matters when selecting a combined oral contraceptive for a patient whose presenting complaint is hirsutism (see Pharmacologic Management). Clinicians should also specifically ask about inadvertent exposure to a partner's or family member's topical testosterone gel, and about valproic acid, which is associated with a PCOS-like phenotype including hirsutism (see the PCOS chapter's Risk Factors).^[1]

• Family history of hirsutism, PCOS, or congenital adrenal hyperplasia in a first-degree relative — particularly relevant for NCCAH, which is inherited in an autosomal recessive pattern (CYP21A2 mutations).
• Ethnic ancestry associated with a higher NCCAH prevalence — Ashkenazi Jewish (up to 37-fold higher), Hispanic, Mediterranean (Spanish, French, Italian), Slavic, or Middle Eastern background — see Recognize the Condition.^[1]
• Obesity/excess adiposity — increases peripheral insulin resistance and ovarian/adrenal androgen production, most relevant to the PCOS-associated pathway (see the PCOS chapter's own Risk Factors for the full mechanism).
• Use of an androgenic or attenuated-androgen medication — danazol, anabolic-androgenic steroids, or a higher-androgenicity progestin — or valproic acid.
• Consanguinity or a known family CYP21A2 mutation — raises pretest probability of NCCAH specifically.
• Rapid-tempo onset around or after puberty — while most adolescent hirsutism reflects an evolving PCOS or idiopathic picture, an unusually early or rapidly progressive presentation still warrants the same red-flag screening used in adults.

Step 1 — confirm hirsutism and exclude hypertrichosis

Score with the modified Ferriman-Gallwey scale (see Recognize the Condition). Local, isolated unwanted hair growth in a eumenorrheic woman with a normal mFG score, and no other clinical evidence of a hyperandrogenic disorder, does not need an androgen work-up — the likelihood of identifying a medical disorder that would change management is low.^[1] A trial of dermatologic/cosmetic therapy alone is reasonable in this situation.

Step 2 — screen for red flags before proceeding routinely

Apply the Red Flags & Referral criteria first; if any is present, proceed directly to imaging and referral rather than the stepwise work-up below.

Step 3 — androgen testing

For a patient with an abnormal mFG score (or local sexual-hair growth accompanied by clinical evidence of a hyperandrogenic disorder), measure total testosterone using a reliable specialty assay — standard automated immunoassays are not sufficiently sensitive at the low concentrations found in women, so use liquid chromatography-tandem mass spectrometry or another validated specialty method where available.^[1] If total testosterone is normal but hirsutism is moderate-to-severe, or there is other clinical evidence of a hyperandrogenic disorder (menstrual disturbance, or progression despite therapy), add free testosterone (calculated from total testosterone and SHBG, or measured by equilibrium dialysis) — free testosterone is more sensitive than total in this situation, since hirsute women commonly have lower SHBG than average, which can mask an elevated bioavailable androgen level on total testosterone alone.^[1]

DHEAS — helping localize an adrenal source

DHEAS originates almost exclusively from the adrenal gland, so a disproportionately elevated DHEAS relative to testosterone points toward an adrenal, rather than ovarian, androgen source. DHEAS is mildly elevated in up to 17% of hirsute women who otherwise have normal total and free testosterone, though a mild elevation in this setting is unlikely on its own to change management.^[1] The magnitude of any androgen elevation, DHEAS included, is a poor predictor of an underlying tumor — but a markedly elevated DHEAS (generally >700 mcg/dL) is suggestive enough to warrant further work-up for an adrenal source.^[1]

17-hydroxyprogesterone — screening for NCCAH

Screen hyperandrogenic women for NCCAH with an early-morning 17-hydroxyprogesterone, drawn in the follicular phase for a regularly cycling patient, or on a random day for a patient with amenorrhea or infrequent menses.^[1] Screen even when total and free testosterone are normal in a patient at high risk for NCCAH — a positive family history, or membership in a higher-prevalence ethnic group (see Recognize the Condition).^[1] A screening 17-hydroxyprogesterone above roughly 170-200 ng/dL (5.15-6.0 nmol/L) is approximately 95% sensitive and 90% specific for NCCAH; a definitive diagnosis requires demonstrating a 17-hydroxyprogesterone of roughly 1000-1500 ng/dL (30-45 nmol/L) or higher, either basally or after cosyntropin stimulation testing, with values in the borderline 1000-1500 ng/dL range confirmed by CYP21A2 genetic testing.^[1]

Excluding PCOS and other causes

Assess menstrual regularity, and where PCOS is suspected apply the Rotterdam criteria per the dedicated PCOS chapter rather than re-deriving them here. Obtain a pregnancy test in any patient with amenorrhea before further work-up, per standard practice. Reserve testing for Cushing syndrome, acromegaly, or hyperprolactinemia for patients with specific clinical features suggestive of these conditions, rather than as routine screening in every hirsute patient.^[1]

Imaging

Reserve pelvic (preferably transvaginal) ultrasound and/or adrenal imaging (CT or another cross-sectional modality) for patients with a red flag (see Red Flags & Referral) — rapid onset/progression, virilization, or markedly elevated androgen levels. Imaging is not indicated for typical, gradual-onset hirsutism with a normal or only mildly elevated androgen level and no virilization.^[1]

• Reduce visible excess hair growth to the degree that matters to the individual patient — patient-important hirsutism is defined by the patient's own distress, not by the Ferriman-Gallwey number alone, and treatment goals should be set accordingly.^[1]
• Identify and address an underlying hormonal cause where one is found — manage confirmed PCOS per the dedicated PCOS chapter, refer confirmed or suspected androgen-secreting tumors promptly, and reserve glucocorticoid therapy for NCCAH to the specific situations described in Special Populations.
• Exclude and refer the red-flag androgen-secreting-tumor differential promptly — rare, but consequential, since over half of these tumors are malignant.^[1]
• Set a realistic timeline with the patient from the outset — meaningful improvement in hair growth takes months, not weeks, because of the long hair growth cycle (see Pharmacologic Management) — so expectations are calibrated before therapy starts rather than after a patient prematurely abandons an effective regimen.
• Support psychological well-being and quality of life directly — hirsutism can be a source of real embarrassment, anxiety, and social avoidance regardless of its objective severity, and this impact deserves explicit acknowledgment as a treatment target in its own right, not only as a physical-exam number.

• Mechanical hair removal — shaving, plucking, and waxing are safe, inexpensive, and have no medical contraindication. A common patient concern — that shaving makes hair grow back thicker, darker, or faster — is a myth worth actively dispelling: depilation has no known effect on the hair follicle itself and does not change hair growth rate, diameter, or color; shaving only yields a bluntly cut tip that can feel coarser on regrowth, creating the illusion of thicker hair.^[1] Plucking, waxing, and other mechanical extraction methods are similarly safe, though they can cause discomfort, folliculitis, scarring, or, particularly in women with darker skin, hyperpigmentation.^[1]
• Chemical depilatories dissolve the hair shaft (usually via a thioglycolate) but commonly cause irritant dermatitis, particularly on the face.
• Photoepilation (laser or intense pulsed light) and electrolysis offer more durable, longer-lasting hair reduction than any mechanical method. Photoepilation targets melanin in the pigmented hair shaft and follicle, so it works well for auburn, brown, or black hair, but is not effective for white or blonde hair, which lacks the pigment target — electrolysis, which does not depend on hair pigment, is the better choice for these patients.^[1] Both methods are somewhat painful and typically require multiple treatments; a topical anesthetic beforehand can reduce discomfort.
• Paradoxical hypertrichosis — a genuinely important, if infrequent, counseling point — is the unexpected occurrence of new hair growth, rather than the expected reduction, after photoepilation. It occurs more often in women with hyperandrogenism and is reported at meaningfully higher rates in patients of Mediterranean or Middle Eastern background undergoing facial photoepilation; consider electrolysis or topical therapy preferentially over photoepilation in this population, and counsel any patient with hyperandrogenism about the possibility before starting laser treatment.^[1]
• For patients with known hyperandrogenemia who choose hair-removal therapy, adding pharmacologic therapy to minimize hair regrowth improves the durability of the cosmetic result — cosmetic and systemic therapy are complementary, not competing, options, and combining them gives a faster, more complete response than either alone.^[1]
• Weight management/lifestyle intervention for a patient with obesity and PCOS-associated hirsutism produces a modest improvement in Ferriman-Gallwey scores, but is not a primary hirsutism therapy on its own — see the PCOS chapter's own lifestyle-intervention guidance, and the dedicated Obesity guideline for pharmacotherapy eligibility if indicated.
• Address the real psychosocial impact directly and explicitly — a brief, direct acknowledgment of the distress hirsutism causes is itself a meaningful intervention, and screening for and addressing significant anxiety or low mood should not be treated as optional.

Pregnancy

Stop spironolactone, cyproterone acetate, and finasteride immediately once pregnancy is confirmed or suspected — all carry a teratogenic risk of feminizing (or, for finasteride, undermasculinizing genital development in) a male fetus.^[1] Mechanical hair removal and photoepilation/electrolysis are reasonable non-hormonal options during pregnancy if cosmetic treatment is still desired. Topical eflornithine has limited pregnancy safety data — use only if the anticipated benefit outweighs the uncertain risk, and prefer non-pharmacologic options where hirsutism is not significantly distressing.

Breastfeeding

Spironolactone has limited breastfeeding safety data and is generally avoided when a non-hormonal or topical alternative (mechanical hair removal, laser, or eflornithine) can adequately control symptoms instead — consistent with the same caution applied in the PCOS chapter. Follow standard postpartum contraceptive-selection guidance (not specific to hirsutism) for COC timing while breastfeeding.

Adolescents

Evaluate an adolescent with hirsutism the same way as an adult, with the same threshold for red-flag screening, but interpret menstrual irregularity cautiously in the first few years after menarche, when cycle irregularity is common and physiologic (see the PCOS chapter's adolescent-specific diagnostic criteria). A combined oral contraceptive remains 1st line pharmacologic therapy in an adolescent who has patient-important hirsutism and no contraindication. The psychosocial impact of hirsutism can be especially significant at this age — screen for and directly acknowledge distress rather than treating it as a secondary concern.

Renal impairment

Use spironolactone with caution, or avoid it, in significant renal impairment given the added hyperkalemia risk from aldosterone-receptor antagonism. Routine potassium monitoring is not necessary in an otherwise healthy young patient on spironolactone without an independent hyperkalemia risk factor (renal disease, an ACE inhibitor/ARB, or a potassium-sparing diuretic).^[1]

Hepatic impairment

Avoid flutamide altogether given its hepatotoxicity risk (see Pharmacologic Management) — this applies with particular force in any patient with pre-existing liver disease. Cyproterone acetate has also been associated with rare hepatotoxicity at higher doses; use with caution and baseline/periodic liver function monitoring in a patient with hepatic impairment.

NCCAH specifically

Treat hirsutism in a patient with confirmed NCCAH the same way as in PCOS: start with a COC, and add an anti-androgen after 6 months if the response is inadequate. Reserve glucocorticoid therapy (for example, prednisone 4-6 mg daily) for hirsutism that responds inadequately to a COC and/or anti-androgen, or that cannot tolerate them — glucocorticoids are more clearly indicated for ovulation induction in NCCAH than for hirsutism itself.^[1] Genetic counseling is relevant for a patient with NCCAH planning pregnancy, given the autosomal recessive inheritance and the possibility of a partner also carrying a CYP21A2 mutation.

Reassess hirsutism only after a full, adequately dosed 6-month trial of any pharmacologic therapy — set this expectation explicitly at the first visit, since visible improvement is genuinely slow and premature reassessment is a common, avoidable source of apparent "treatment failure."^[1] Photographic documentation at baseline and follow-up can help both patient and clinician track a genuinely slow-moving change more objectively than memory alone. For a patient on an anti-androgen, confirm reliable contraception remains in place at every visit, not only at the first prescription — this is an ongoing counseling point, not a one-time check. For a patient with confirmed NCCAH, an androgen-secreting tumor, or another hormonal cause under specialist follow-up, coordinate monitoring rather than duplicating it. Ask directly, at every visit, about the psychosocial impact of both the hirsutism itself and its treatment — this does not reliably track the physical exam alone. For a patient using topical eflornithine, remind them that hair growth returns to the pretreatment rate within about 8 weeks of stopping, so continued application, not a finite course, is required to maintain effect.^[1]

1. Confirm adherence and that a full 6-month trial has actually elapsed before concluding any pharmacologic therapy has failed — this is the single most common reason a genuinely effective regimen looks like it isn't working.
2. If a COC alone has not adequately controlled patient-important hirsutism after 6 months, add spironolactone (with reliable contraception already in place) rather than switching COC formulations repeatedly — no COC has been shown clearly superior to another for hirsutism.
3. If a COC plus spironolactone at an adequate dose (up to 200 mg/day) and duration remains inadequate, consider switching to cyproterone acetate (as the fixed-dose COC or the standalone reverse-sequential regimen) with explicit VTE counseling, or add topical eflornithine and/or laser/electrolysis as an adjunct.
4. If hirsutism progresses despite an adequately dosed, adequately trialed regimen — rather than simply remaining unchanged — re-examine for a red flag (rapid pace, virilization, markedly elevated androgens) that may have been missed initially, and refer for imaging if any is present.
5. If NCCAH has been confirmed and hirsutism remains inadequately controlled by a COC and/or anti-androgen, consider adding glucocorticoid therapy, reserved for this situation rather than used as first-line therapy for hirsutism itself.
6. If severe hyperandrogenemia (for example, ovarian hyperthecosis) has not responded adequately to a COC plus anti-androgen, refer for consideration of a GnRH agonist with estrogen add-back under specialist supervision.
7. Persistent, significant psychological distress despite an objectively adequate response: address it directly — quality-of-life impact is itself a legitimate reason to intensify cosmetic therapy (laser/electrolysis) or seek additional support, not only a secondary consideration to hair count.

• Diagnosing PCOS, or dismissing hirsutism as "just PCOS," without actively considering NCCAH — especially in a patient from a higher-risk ethnic group or with a positive family history — since NCCAH can look identical to PCOS on the surface.
• Judging a COC or spironolactone trial a failure before a full 6 months has elapsed — hair growth is slow, and premature discontinuation is one of the most avoidable reasons a genuinely effective regimen appears not to work.
• Reassuring a patient that shaving or plucking will make hair grow back thicker or darker — this is a myth that can needlessly deter a patient from a safe, effective cosmetic option.
• Using flutamide for hirsutism given its hepatotoxicity risk, even at a low dose.
• Starting or continuing any anti-androgen (spironolactone, cyproterone acetate, finasteride) without first confirming reliable contraception is in place.
• Treating eflornithine as an anti-androgen, or as a cure — it works by a different, direct mechanism, must be continued to maintain effect, and hair growth returns to baseline within about 8 weeks of stopping.
• Recommending metformin specifically to treat hirsutism — it is not superior to placebo for this indication; its role is confined to the metabolic phenotype of PCOS.
• Dismissing a red flag (rapid onset, virilization) because the testosterone or DHEAS level is only moderately elevated — tumor androgen output does not always correlate with tumor severity or malignancy risk.
• Ordering a full hormone panel and pelvic ultrasound routinely for mild, localized, gradual-onset hair growth with a normal exam and no red flags — this is not indicated and adds cost and anxiety without benefit.
• Overlooking the real psychological impact of hirsutism because the Ferriman-Gallwey score is low — patient-important hirsutism is defined by the patient's own distress, not the number.

How to use this table: doses are adult doses and require patient-specific confirmation, including renal/hepatic adjustment. Every anti-androgen row assumes effective contraception is already in place — see Choose Initial Treatment. Select any drug name to open its complete Pharmasist Drug Database page.

Combined hormonal contraceptives

1st line for most patients not seeking pregnancy. No single formulation has been shown clearly superior for hirsutism; anti-androgenic progestins are commonly selected specifically when hirsutism is the dominant complaint.

Evidence note: the elevated VTE signal specific to cyproterone acetate/ethinyl estradiol is confirmed by a Health Canada summary safety review.^[4]

Anti-androgens

Add after patient-important hirsutism persists despite an adequate (at least 6 month) COC trial, or as initial combination therapy in select cases of severe, distressing hirsutism. Always combine with effective contraception given teratogenic risk.

Topical, direct-acting therapy

Facial hirsutism specifically. Acts directly on the hair follicle rather than on circulating hormones, so it can be used as monotherapy for mild cases or layered onto any systemic regimen above for a faster, more complete response.

Not recommended for hirsutism

Included here specifically because a pharmacist may otherwise expect these agents to be reasonable options.

Evidence note: the Endocrine Society's 2018 guideline update strengthened its recommendation against flutamide for hirsutism specifically because of accumulating hepatotoxicity reports, and separately recommends against insulin-lowering drugs (e.g., metformin) and topical anti-androgen creams for this indication.^[1]

Note: glucocorticoid therapy for NCCAH-associated hirsutism, and GnRH agonist therapy for severe hyperandrogenemia unresponsive to standard therapy, are reserved specialist-directed options — see Special Populations and Treatment Failure/Next Step rather than a routine drug-table entry here.