Hirsutism
Exam Tips
- Differentiate hirsutism (androgen-pattern terminal hair) from hypertrichosis (diffuse nonsexual pattern) early in OSCE stations.
- Use Ferriman-Gallwey scoring but explain limitations: ethnicity variation, prior hair removal, and mismatch between score and patient distress.
- Red flags for urgent endocrine referral: rapid onset, virilization, pelvic/abdominal mass, or markedly elevated testosterone.
- In UK exams, mention total testosterone first-line, then early morning free/total testosterone and follicular-phase 17-hydroxyprogesterone when indicated.
- State safety explicitly: anti-androgens require reliable contraception due to fetal risk; assess VTE risk before oestrogen-containing therapy.
- Image cue: revise Ferriman-Gallwey site map and terminal vs vellus hair examples (DermNet/NICE-linked images) before clinical exams.
Definition
Hirsutism is excessive growth of coarse, pigmented terminal hair in androgen-sensitive areas in women, such as the face, chest, lower abdomen, back, upper arms, and thighs. It reflects either androgen excess or increased follicular sensitivity to normal androgen concentrations, and should be distinguished from generalized non-androgenic hair overgrowth (hypertrichosis).
Pathophysiology
Androgens (mainly testosterone and its more potent metabolite dihydrotestosterone, DHT) act on pilosebaceous units to convert fine vellus hair into terminal hair in androgen-dependent skin. Hirsutism results from one or more mechanisms: increased circulating androgens (most commonly in PCOS), increased local 5-alpha-reductase activity with enhanced conversion of testosterone to DHT, increased androgen receptor sensitivity, and altered peripheral androgen metabolism. In idiopathic hirsutism, ovulatory cycles and serum androgens are often normal, suggesting predominantly peripheral follicular hypersensitivity. See Figure: Ferriman-Gallwey body map and pilosebaceous unit androgen pathway diagrams in standard dermatology/endocrinology texts.
Risk Factors
- Polycystic ovary syndrome (most common cause, >70% of cases)
- Family history of hirsutism or hyperandrogenism
- Ethnicity (higher prevalence in Mediterranean and Middle Eastern populations)
- Drugs causing androgenic effect (for example anabolic steroids, danazol, sodium valproate, ciclosporin, phenytoin, tamoxifen)
- Non-classical congenital adrenal hyperplasia
- Androgen-secreting adrenal or ovarian tumours
- Cushing's syndrome, acromegaly, thyroid dysfunction, hyperprolactinaemia
- Menopausal hormonal change (relative increase in androgen effect due to lower oestrogen/progesterone)
Clinical Features
Symptoms
- Progressive unwanted coarse hair growth in androgen-dependent sites
- Menstrual irregularity (oligomenorrhoea/amenorrhoea)
- Subfertility/infertility
- Acne or oily skin
- Psychological distress, low self-esteem, social withdrawal, depressive symptoms
Signs
- Terminal (stiff, pigmented) hair in androgen-sensitive distribution
- Ferriman-Gallwey score elevation (commonly >=8 in UK Black/White reproductive-age women, but interpret by ethnicity and context)
- PCOS-associated features: central adiposity, acanthosis nigricans
- Virilization red flags: deep voice, clitoromegaly, temporal scalp hair loss, increased muscle bulk
- Signs suggesting endocrine disease: moon facies, proximal myopathy, purple striae (Cushing syndrome); galactorrhoea (hyperprolactinaemia); enlarged hands/mandible/frontal bossing (acromegaly)
Investigations
Management
Lifestyle Modifications
- Provide empathetic counselling; assess mental health impact and quality-of-life burden as part of routine care.
- Weight reduction and exercise in overweight women with PCOS can improve insulin resistance, ovulatory function, and androgenic symptoms.
- Offer cosmetic/physical hair-removal options (shaving, waxing, depilatories, bleaching, laser/photoepilation, electrolysis) based on preference, skin/hair type, and cost.
- Urgently refer (2-week pathway) if sudden onset, rapid progression, virilization, pelvic/abdominal mass, or markedly raised testosterone suggests androgen-secreting tumour.
- Refer to endocrinology for abnormal hormonal investigations or suspected complex endocrine pathology.
Pharmacological Treatment
Combined oral hormonal therapy (first-line when contraception acceptable)
- Ethinylestradiol/cyproterone acetate 35 micrograms/2 mg (co-cyprindiol): 1 tablet daily for 21 days, then 7-day break
Improves hirsutism over months by suppressing ovarian androgen production and increasing SHBG. Use lowest VTE-risk appropriate COC strategy and review thromboembolic risk, smoking status, migraine history, BMI, and age. Co-cyprindiol is generally reserved for severe androgen-sensitive conditions when other options are unsuitable; stop when symptoms controlled where possible.
Topical anti-hair-growth agent
- Eflornithine 11.5% cream: apply thinly to affected facial areas twice daily, at least 8 hours apart
Adjunct for facial hirsutism; slows hair growth rather than removing hair. Assess response after about 4 months. Avoid contact with eyes/mucosa; local irritation can occur.
Anti-androgens (specialist or experienced prescriber, often second-line/add-on)
- Spironolactone 50-100 mg once daily, titrated to 100-200 mg/day if needed
- Finasteride 2.5-5 mg once daily (off-label for women)
Both are teratogenic to a male fetus; ensure effective contraception and avoid in pregnancy. Monitor potassium and renal function with spironolactone; caution with ACE inhibitors/ARBs and renal impairment. Finasteride is contraindicated in pregnancy; tablets should not be handled if crushed/broken by pregnant individuals.
Insulin-sensitizing therapy in PCOS (for metabolic/reproductive indications)
- Metformin immediate-release 500 mg once daily with food, increasing gradually (for example by 500 mg weekly) to 1.5-2 g/day in divided doses as tolerated
Not a primary cosmetic anti-hirsutism drug, but may help broader PCOS phenotype. GI adverse effects are common; check renal function and avoid if severe renal impairment. Consider B12 monitoring with long-term use.
Surgical / Interventional
- Definitive treatment of underlying tumour cause (for example adrenalectomy or ovarian tumour resection) when an androgen-secreting neoplasm is confirmed.
- No routine surgery for idiopathic/PCOS-related hirsutism; procedural hair reduction is usually via laser or electrolysis rather than surgery.
Complications
- Psychological morbidity (anxiety, depression, reduced self-esteem)
- Social and relationship difficulties with major quality-of-life impairment
- Complications of underlying disease if missed (for example tumour progression, untreated Cushing syndrome, metabolic complications of PCOS)
- Medication-related adverse effects (for example VTE risk with oestrogen-containing therapy, hyperkalaemia with spironolactone, teratogenic risk with anti-androgens)
Prognosis
Prognosis depends on cause and treatment adherence. Idiopathic and PCOS-related hirsutism are usually chronic but manageable; visible improvement from hormonal therapy often takes 6-12 months, and relapse can occur after stopping treatment. Prognosis is excellent if serious secondary causes are identified early and treated appropriately.
Sources & References
✅NICE Guidelines(1)
- Hirsutism[overview]