What is the recommended dosage of Aldactone (spironolactone) for a female patient with androgenetic alopecia?

Aldactone (Spironolactone) Dosage for Female Androgenetic Alopecia

Start with 50-100 mg daily and titrate up to 200 mg daily if needed after 3 months, with maximum response expected at 5-6 months of treatment. 1, 2

Initial Dosing Strategy

• Begin with 50-100 mg daily taken in the evening as the standard starting dose for female pattern hair loss 1, 2
• Lower starting doses (50 mg daily) are preferred to minimize side effects, particularly menstrual irregularities, while maintaining efficacy 3, 4
• The American Academy of Dermatology confirms that 50-200 mg orally daily is the appropriate dosing range for off-label dermatologic use 5

Dose Escalation Protocol

• Wait at least 3 months before increasing the dose, as initial response typically occurs around this timeframe 1
• If inadequate response at 3 months, increase in 25-50 mg increments every 3 months 1
• Maximum dose is typically 200 mg daily, as higher doses increase side effects disproportionately to therapeutic benefit without additional efficacy 1, 2
• Studies show that 84% of patients initially improve at 100 mg/day, with additional patients responding to dose increases up to 150 mg/day 1

Timeline for Response

• Expect 3 months for initial response and 5-6 months for maximum therapeutic benefit 1, 2
• Treatment duration of at least 6-12 months is necessary to properly assess response 2
• Hair regrowth may plateau after 12-24 months, at which point combination therapy with topical minoxidil 5% can provide additive benefit 6

Mandatory Concurrent Contraception

• Combined oral contraceptives (COCs) must be prescribed concurrently to prevent pregnancy (Category C), regulate menstrual cycles, and minimize menstrual irregularities 1, 2
• Spironolactone can be safely combined with drospirenone-containing COCs without causing hyperkalemia 1
• Pregnancy testing is absolutely required before starting treatment, as spironolactone may cause feminization of male fetuses 2

Monitoring Requirements

Baseline Assessment:

• Serum potassium, sodium, and renal function 5, 2
• Blood pressure 5
• Pregnancy test 2

Ongoing Monitoring:

• Routine potassium monitoring is NOT required in young, healthy women without comorbidities 1, 2
• Monitor potassium at baseline, 1 week, 4 weeks, and after dose increases in older patients, those with hypertension, diabetes, chronic kidney disease, or those taking ACE inhibitors, ARBs, or NSAIDs 1, 2

Common Side Effects and Management

• Menstrual irregularities occur in 15-30% of patients and are dose-dependent, with relative risk of 4.12 at 200 mg/day compared to lower doses 1
• Concurrent COC or hormonal IUD use minimizes menstrual irregularities 1
• Other side effects include breast tenderness (3-5%), dizziness (3-4%), nausea (2-4%), headache (2%), and decreased libido 1
• At higher doses (200 mg daily), metrorrhagia with shortened cycles occurred in 56% of women in one study, often requiring dose reduction 3

Absolute Contraindications

• Pregnancy 5, 2
• Acute renal failure or significant renal impairment 5, 2
• Hyperkalemia 5, 2
• Addison disease 5, 2
• Anuria 5, 2
• Concomitant use of eplerenone or triamterene 5, 2

Critical Drug Interactions

• ACE inhibitors and angiotensin II receptor blockers (increased hyperkalemia risk) 5, 2
• Potassium supplements or potassium-sparing diuretics 5, 2
• NSAIDs 5, 2
• Digoxin 5, 2

Combination Therapy Considerations

• Topical minoxidil 5% twice daily can be added if response plateaus after 12-24 months of spironolactone monotherapy 6
• Combination therapy shows better efficacy than monotherapy for androgenetic alopecia 7
• Topical spironolactone (1% gel or 5% solution twice daily) is an alternative with significantly fewer systemic side effects, though oral formulations remain more commonly used 7

Important Clinical Caveats

• Treatment is palliative, not curative—discontinuation typically leads to recurrence, requiring long-term commitment 2
• Avoid use in postmenopausal women due to risks of hyperkalemia and cardiovascular complications that outweigh benefits 2
• Large cohort studies of 4.5 million patients show no increased cancer risk with long-term use, despite black box warnings from animal studies 1, 2