I am a woman with excess terminal hair on the nipples and chin and normal androgen levels; what is the likely diagnosis and how should it be evaluated and treated?

Likely Diagnosis: Idiopathic (Normoandrogenic) Hirsutism

Your presentation of terminal hair on the nipples and chin with normal androgen levels most likely represents idiopathic hirsutism, which accounts for 5–10% of hirsutism cases and is characterized by normal ovulatory function, normal serum androgens, and normal ovarian morphology. 1, 2

Understanding Your Condition

What "Normal" Androgens Actually Mean

• Women with idiopathic hirsutism demonstrate relative hyperandrogenemia—meaning your androgen levels, although within the laboratory reference range, are higher than those of women without hirsutism. 3
• The pilosebaceous unit (hair follicle complex) in affected areas shows increased local androgen production through higher expression of steroid sulphatase and 17-beta hydroxysteroid dehydrogenase, which convert weak androgens into more potent forms directly in the skin. 3
• This explains why you have terminal hair growth despite "normal" blood tests: the problem is increased local tissue sensitivity and metabolism rather than systemic androgen excess. 3, 4

Important Caveat About the Diagnosis

• Idiopathic hirsutism may represent an early stage of polycystic ovary syndrome (PCOS) rather than a distinct entity, so ongoing monitoring is warranted. 3
• PCOS accounts for 70–80% of all hirsutism cases, so even with currently normal labs, you should be reassessed if you develop menstrual irregularities, weight gain, or acne. 1, 2

Complete Evaluation You Should Receive

Clinical Assessment Required

• Menstrual history: Cycles shorter than 23 days (polymenorrhea), longer than 35 days (oligomenorrhea), or absent for >6 months (amenorrhea) suggest underlying endocrine dysfunction and would shift the diagnosis toward PCOS. 1
• Metabolic signs: Waist-hip ratio >0.9 (truncal obesity) or acanthosis nigricans (dark, velvety skin in neck/axillae) indicate insulin resistance. 1
• Red-flag features: Buffalo hump, moon-shaped face, and wide violaceous striae suggest Cushing's syndrome and require endocrinology referral. 1
• Rapid progression: Symptoms developing over weeks to months, deepening voice, or clitoromegaly raise concern for androgen-secreting tumors. 1, 5

Laboratory Testing Algorithm

First-line tests (should have been done):

• Total testosterone and free testosterone measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the morning—sensitivity 74% and 89%, respectively. 5
• DHEAS to assess adrenal androgen production. 5
• Prolactin and TSH to exclude hyperprolactinemia and thyroid disease. 5

Second-line tests (if clinical suspicion remains high despite normal first-line results):

• Androstenedione (sensitivity 75%, specificity 71%). 5
• 17-hydroxyprogesterone to rule out non-classical congenital adrenal hyperplasia. 1, 6

Metabolic screening (essential even with normal androgens):

• Fasting glucose followed by 2-hour oral glucose tolerance test with 75-gram glucose load. 5
• Fasting lipid panel (total cholesterol, LDL, HDL, triglycerides). 5

Imaging Considerations

• Pelvic ultrasound is not routinely indicated for idiopathic hirsutism with normal ovulatory function, but should be performed if you develop oligomenorrhea or other PCOS features. 1
• Adrenal CT is mandatory only if DHEAS >600 μg/dL or signs of severe virilization are present. 6

Treatment Strategy

Medical Therapy Options

First-line: Combined oral contraceptives (COCs)

• COCs suppress ovarian androgen production, increase sex hormone-binding globulin, reduce 5-alpha-reductase activity, and block androgen receptors. 1
• Avoid COCs containing androgenic progestins (norethisterone derivatives, levonorgestrel) as they worsen hirsutism. 1
• Improvement in hirsutism typically requires 6–12 months of continuous therapy. 1
• Contraindications: Smoking ≥15 cigarettes/day at age ≥35, uncontrolled hypertension (≥160/100 mmHg), history of venous thromboembolism or ischemic heart disease. 1

Second-line: Spironolactone

• Add spironolactone 50–100 mg daily if COCs alone are insufficient after 6 months. 1
• Achieves clear skin or marked improvement in 66–85% of women. 1
• Can be safely combined with COCs without clinically significant hyperkalemia risk. 1

Alternative anti-androgens (if spironolactone not tolerated):

• Finasteride, flutamide, or cyproterone acetate can be used. 1

Mechanical Hair Removal

• Topical eflornithine hydrochloride cream slows hair regrowth and can be used alongside systemic therapy. 1
• Laser hair removal offers the fastest mechanical method, though effectiveness depends on skin type, hair color, and practitioner skill. 4
• Shaving, waxing, plucking, and electrolysis are additional options. 1, 4

Lifestyle Modifications

• If you are overweight, a 5% weight reduction can improve metabolic and reproductive abnormalities. 1
• Consider metformin 500 mg three times daily if you have insulin resistance features (obesity, acanthosis nigricans). 1

Critical Pitfalls to Avoid

• Do not dismiss your symptoms because androgens are "normal"—hirsutism causes significant psychological distress and quality-of-life impairment regardless of laboratory values. 2, 7
• Do not expect rapid improvement—medical therapy requires at least 3–6 months before visible benefit, and lifelong treatment may be needed to prevent recurrence. 7
• Do not use topical or systemic antibiotics for associated acne without benzoyl peroxide, as this promotes bacterial resistance. 1
• Do not assume the diagnosis is permanent—you require ongoing monitoring because idiopathic hirsutism may evolve into PCOS over time. 3

Recommended Follow-Up

• Reassess at 3–6 months after starting COCs to evaluate hirsutism response and metabolic parameters. 1
• Repeat androgen testing if you develop new symptoms (menstrual irregularity, rapid hair growth, voice changes). 1, 5
• Annual metabolic screening (glucose, lipids) is prudent given the potential overlap with PCOS. 5