How it works
Spironolactone blocks aldosterone at its receptors (mineralocorticoid receptors). It also blocks the androgen receptor. Blocking androgens is why it helps with skin problems and PCOS.
The evidence
Dermatologists have long used it off-label for acne in adult women. Several cohort studies (studies that follow groups of patients over time) support it at 50–200 mg daily. Versions you put on the skin are also used for hormonal acne. They're expected to cause fewer whole-body side effects, but the evidence for them is more limited.
Typical dosing
Pill: 50–100 mg daily. The dose can be raised slowly to 200 mg. On the skin: usually a 5% formula, once a day.
Side effects
Common
- Peeing more (oral)
- Irregular periods (oral)
- Breast tenderness (oral)
Less common
- High potassium (oral)
- Dizziness
Rare
- Severe high potassium in people with kidney problems
Drug interactions
- ACE inhibitors / ARBs: risk of high potassium
- Potassium supplements: risk of high potassium
- NSAIDs (like ibuprofen): it may work less well, and it's harder on the kidneys
