Dydrogesterone
孕激素 C
Dydrogesterone
Dydrogesterone
Oral
Dydrogesterone is a retro-isomer of progesterone with significantly higher oral bioavailability than micronized progesterone. Used as an alternative progestogen option in transfeminine HRT, though clinical evidence specific to transgender care remains limited [1] .
Mechanism
Section titled “Mechanism”Dydrogesterone is a structural analog of natural progesterone with highly selective progestogenic receptor activity:
- High oral bioavailability: ~28% (vs ~10% for micronized progesterone)
- No anti-androgenic activity: Unlike CPA or spironolactone, does not directly affect androgens
- No glucocorticoid or mineralocorticoid activity
- Half-life: ~14-17 hours
Comparison with Micronized Progesterone
Section titled “Comparison with Micronized Progesterone”| Feature | Dydrogesterone | Micronized Progesterone |
|---|---|---|
| Type | Retro-isomer (synthetic) | Natural/bioidentical |
| Oral bioavailability | ~28% | ~10% |
| Sedative effect | Minimal | Significant (hence bedtime dosing) |
| Routes | Oral only | Oral/rectal/vaginal |
| VTE risk | Insufficient data | Neutral or very low |
| Evidence level | C | C |
Dosing
Section titled “Dosing”| Indication | Dose | Notes |
|---|---|---|
| HRT progestogen supplementation | 10-20 mg/day | Usually 1-2 times daily |
| Cyclic regimen | 10 mg/day x 14 days/month | Mimics luteal phase of menstrual cycle |
Brands & Availability
Section titled “Brands & Availability”| Brand | Strength | Region |
|---|---|---|
| Duphaston | 10 mg | Widely available globally (including mainland China) |
| Generics | 10 mg | Select regions |
Monitoring
Section titled “Monitoring”- PRL (prolactin): Every 6 months. Progestogens may mildly elevate prolactin
- No additional liver monitoring needed (dydrogesterone has very low hepatotoxicity)
Contraindications
Section titled “Contraindications”- Dydrogesterone allergy
- Unexplained vaginal bleeding (cisgender indication — rarely applicable in trans context)
- Acute hepatic porphyria