Hirsutism
Clinical Snapshot
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]
Recognize the Condition
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]
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]
Risk Factors
- 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.
Red Flags & Refer
Most hirsutism reflects PCOS, idiopathic hirsutism, or a straightforward medication cause. Escalate for prompt imaging and specialist (gynecology/endocrinology) referral instead of routine outpatient management when any of the following is present:
- Rapid onset or rapid progression — hirsutism developing or clearly worsening over weeks to a few months, rather than gradually over years.
- Signs of frank virilization — clitoromegaly, deepening of the voice, temporal (male-pattern) balding, or a marked, disproportionate increase in muscle mass — any of these, alone or in combination, points toward an androgen-secreting tumor rather than PCOS or idiopathic hirsutism.[1]
- Markedly elevated androgen levels — a total testosterone in the adult-male range, or a substantially elevated DHEAS (generally >700 mcg/dL, roughly >19 micromol/L) — though the magnitude of the elevation is an imperfect predictor: some androgen-secreting tumors produce only moderately elevated androgen levels and still present indolently, so a red flag on history or exam should not be dismissed just because the androgen level is not dramatically high.[1]
- Progression despite adequate therapy — hirsutism that keeps advancing despite a correctly dosed, adequately trialed (at least 6 months) pharmacologic regimen.
- Features suggesting Cushing syndrome instead — proximal muscle weakness, wide violaceous striae, easy bruising, a rapidly progressive centripetal weight-gain pattern.
Any of these findings warrants pelvic (transvaginal) ultrasound and/or adrenal imaging to exclude an androgen-secreting tumor. Some androgen-secreting ovarian tumors are too small to be reliably detected on transvaginal ultrasound[1] — a clean initial imaging study does not fully exclude the diagnosis if the clinical picture remains strongly suggestive, and specialist referral should proceed regardless.
Assessment & Diagnosis
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]
Treatment Targets
- 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.
Choose Initial Treatment
Set expectations before starting
Hair growth is slow and nonsynchronous — the growth (anagen) phase for facial hair lasts about 4 months, so it takes about 6 months to detect the effect of a new hormonal therapy and up to about 9 months for the effect to become maximal.[1] Trial every pharmacologic therapy for at least 6 months before judging it inadequate, changing the dose, switching agents, or adding a second agent.[1] State this explicitly at the first visit — premature discontinuation of an agent that was actually working is one of the most avoidable failures in hirsutism management.
Not seeking pregnancy
1st line, most patients a combined oral contraceptive — no single formulation has been shown clearly superior to another for hirsutism in most patients, so selection can be individualized on side-effect profile, cost, and preference; for a patient at higher risk of venous thromboembolism (obesity, or age over 39), prefer the lowest effective ethinyl estradiol dose (usually 20 mcg) with a low-VTE-risk progestin.[1]
Patient-important hirsutism persisting after an adequate (≥6 month) trial of a COC alone add an anti-androgen — spironolactone is the most commonly used first choice. No anti-androgen has been shown clearly superior to another as a class, but flutamide should not be used given its hepatotoxicity risk (see Pharmacologic Management).[1]
Never start any anti-androgen without effective contraception already in place — every anti-androgen carries a teratogenic risk of feminizing a male fetus. The only exceptions are a patient who is not sexually active, has undergone permanent sterilization, or is using a long-acting reversible contraceptive — in these situations either a COC or an anti-androgen may reasonably be used as initial therapy.[1]
Severe hirsutism causing significant emotional distress, or a patient who has already tried a COC alone without sufficient improvement starting combination therapy with a COC and an anti-androgen together is a reasonable option — but combination therapy is not recommended as a standard first-line approach for most patients.[1]
Mild hirsutism, no evidence of an endocrine disorder
Either approach is reasonable pharmacologic therapy or direct hair-removal methods alone — there is no strong evidence favouring one over the other in this specific group.[1]
Cosmetically distressing, faster response desired
Add topical eflornithine to photoepilation, or use it as monotherapy for mild facial hirsutism — it acts directly on the hair follicle, not on circulating hormones, and can be layered onto any systemic regimen above.
Not to use for hirsutism
Insulin-lowering drugs (e.g., metformin) for the sole purpose of treating hirsutism — meta-analysis shows no benefit over placebo for hirsutism scores specifically; reserve metformin for its actual PCOS metabolic indication (see the PCOS chapter).[1] Topical anti-androgen creams — limited and inconsistent efficacy evidence; this does not include eflornithine, which works by a different, direct mechanism and is genuinely effective.[1] GnRH agonists outside of severe hyperandrogenemia (for example, ovarian hyperthecosis) with a suboptimal response to a COC plus anti-androgen — expensive, injectable, and requires estrogen add-back to avoid rapid bone loss, without a demonstrated advantage over standard therapy.[1]
Non-Pharmacologic Treatment
- 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.
Special Populations
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.
Monitoring & Follow-Up
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]
Common Errors to Avoid
- 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.
Clinical Decision Algorithm
Drug Tables
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.
| Drug | Dosage | Adverse effects | Drug interactions | Comments |
|---|---|---|---|---|
| Levonorgestrel/ethinyl estradiol | Cyclic: 1 tablet PO daily for 21 days, then 7 hormone-free days Continuous/extended-cycle: 1 tablet PO daily on a continuous or extended schedule per product labeling | Breakthrough bleeding, breast tenderness, nausea, headache; rare venous thromboembolism. | Enzyme-inducing drugs (certain anticonvulsants, rifampin, St. John's wort) may reduce contraceptive efficacy. | Standard first choice, particularly for a patient at higher VTE risk (obesity, age over 39) using the lowest effective ethinyl estradiol dose. |
| Drospirenone/ethinyl estradiol | Dosing: 1 tablet PO daily for 21 days, then 7 hormone-free days | Breakthrough bleeding, mood changes, breast tenderness, hyperkalemia risk. | Additive hyperkalemia risk with ACE inhibitors, ARBs, potassium-sparing diuretics, or NSAIDs. | Anti-androgenic (antimineralocorticoid) progestin; a common choice when hirsutism is prominent. Check potassium if an additional hyperkalemia risk factor is present. |
| Cyproterone acetate/ethinyl estradiol | Dosing: 1 tablet PO daily for 21 days, then 7 hormone-free days | Breakthrough bleeding, mood changes, breast tenderness. | None significant beyond the general COC class. | The most potent anti-androgenic fixed-dose COC. Health Canada's safety review confirms an elevated venous thromboembolism signal relative to other COCs — reserve for hirsutism unresponsive to a standard COC, and counsel VTE symptoms (unilateral leg swelling/pain, sudden shortness of breath or chest pain) explicitly. |
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.
| Drug | Dosage | Adverse effects | Drug interactions | Comments |
|---|---|---|---|---|
| Spironolactone | Dosing: 50-100 mg PO BID Maximum: 200 mg/day in divided doses | Menstrual irregularity if not combined with a COC, breast tenderness, hyperkalemia (chiefly with an additional risk factor), occasional postural hypotension/dizziness early in treatment. | Additive hyperkalemia risk with ACE inhibitors, ARBs, potassium-sparing diuretics, potassium supplements, or NSAIDs. | Most commonly used first anti-androgen. Effect on hair growth takes at least 6 months to assess. Requires effective contraception — teratogenic feminization risk to a male fetus. Routine potassium monitoring is not necessary in an otherwise healthy young patient without an independent hyperkalemia risk factor. |
| Cyproterone acetate | Dosing: 50-100 mg PO daily on cycle days 5-15 With: Ethinyl estradiol 20-35 mcg PO daily on cycle days 5-25 | Similar profile to the combined product — breakthrough bleeding, mood changes, breast tenderness; rare hepatotoxicity at higher doses. | None significant beyond the general anti-androgen class. | A more potent classic reverse-sequential regimen, distinct from the fixed-dose 2 mg CPA/35 mcg EE COC product; available in Canada but not the United States. |
| Finasteride | Dosing: 2.5-5 mg PO once daily | Generally well tolerated; teratogenic — blocks conversion of testosterone to dihydrotestosterone, a risk to a male fetus. | None significant at standard doses. | Alternative anti-androgen with a more limited evidence base than spironolactone or cyproterone acetate; reduces hirsutism scores by roughly 30-60% in available trials. Off-label for this indication. |
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.
| Drug | Dosage | Adverse effects | Drug interactions | Comments |
|---|---|---|---|---|
| Eflornithine cream | Dosing: Apply a thin layer to affected facial areas BID, at least 8 hours apart | Local skin irritation, stinging, acne-like eruptions at the application site. | None significant — topical, minimal systemic absorption. | Not an anti-androgen — irreversibly inhibits ornithine decarboxylase, the rate-limiting enzyme for follicular hair growth. Visible benefit in 6-8 weeks; hair growth returns to the pretreatment rate within about 8 weeks of stopping — ongoing application, not a finite course, is required to maintain effect. |
Not recommended for hirsutism
Included here specifically because a pharmacist may otherwise expect these agents to be reasonable options.
| Drug | Dosage | Adverse effects | Drug interactions | Comments |
|---|---|---|---|---|
| Flutamide | Not applicable: No dose is recommended for this indication | Hepatotoxicity, including reported liver failure, transplantation, and death, even at low doses. | None significant at doses studied for hirsutism — the concern is hepatotoxicity, not drug interactions. | A potent anti-androgen, but not recommended for hirsutism given its hepatotoxicity risk — the Endocrine Society issued a strengthened recommendation against its use even at low (62.5-250 mg/day) doses. |
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.
References
- Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline — Journal of Clinical Endocrinology & Metabolism, Endocrine Society (Martin KA, Anderson RR, Chang RJ, Ehrmann DA, Lobo RA, Murad MH, Pugeat M, Rosenfield RL). J Clin Endocrinol Metab 2018;103(4):1233-1257
- Guideline No. 444: Hirsutism: Evaluation and Treatment — Journal of Obstetrics and Gynaecology Canada, Society of Obstetricians and Gynaecologists of Canada (Elliott J, Liu K, Motan T). J Obstet Gynaecol Can 2023;45(12):102272
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Professional reference only. Apply clinical judgment and verify patient-specific decisions against current authoritative guidance and product information.