Conjugated Estrogens (0.625mg) is a preparation of naturally derived, water-soluble, conjugated estrogens obtained from the urine of pregnant mares. It contains a mixture of sodium estrone sulfate and sodium equilin sulfate as the principal components. It is a systemic estrogen hormone replacement therapy (HRT) used primarily for managing menopausal symptoms and preventing postmenopausal osteoporosis in the Indian context. Its effects are mediated through binding to intracellular estrogen receptors.
Adult: For vasomotor symptoms/vaginal atrophy: 0.3mg to 1.25mg daily, cyclically (e.g., 21-25 days on, 5-7 days off) or continuously. The standard starting dose is 0.625mg daily. For osteoporosis prevention: 0.625mg daily. Women with an intact uterus MUST receive a progestogen for at least 12-14 days per cycle to prevent endometrial hyperplasia.
Note: Take orally, once daily, with or without food. For cyclic therapy, take as prescribed (e.g., 21 days on, 7 days off). For continuous therapy, take daily without a break. If a dose is missed, take it as soon as remembered. If it is near the time for the next dose, skip the missed dose. Do not double the dose.
Conjugated estrogens exert their effects by diffusing into target cells and binding with high affinity to nuclear estrogen receptors (ERΞ± and ERΞ²). The hormone-receptor complex undergoes dimerization, binds to specific DNA sequences (Estrogen Response Elements - EREs), and regulates the transcription of target genes. This genomic action leads to the synthesis of proteins responsible for the therapeutic effects.
Pregnancy: CATEGORY X. Contraindicated. May cause fetal harm. Use during pregnancy is associated with clear risks (e.g., vaginal adenosis, clear cell carcinoma of the vagina/cervix in female offspring) that outweigh any benefit.
Driving: Usually no effect. However, patients who experience dizziness, migraine, or visual disturbances should exercise caution.
| Carbamazepine, Phenytoin, Rifampicin | Induce CYP3A4, increasing estrogen metabolism, leading to reduced efficacy and potential breakthrough bleeding. | Major |
| Ketoconazole, Itraconazole, Erythromycin | Inhibit CYP3A4, potentially increasing estrogen levels and risk of adverse effects. | Moderate |
| Warfarin, Acenocoumarol | Estrogens may alter coagulation factors; can decrease or increase anticoagulant effect. Monitor INR closely. | Major |
| Thyroid Hormones (Levothyroxine) | Estrogens may increase thyroxine-binding globulin, potentially requiring an increase in levothyroxine dose. | Moderate |
| Corticosteroids | Estrogens may potentiate the anti-inflammatory effects and side effects of corticosteroids. | Moderate |
| St. John's Wort | Induces metabolism, reducing estrogen efficacy and causing breakthrough bleeding. | Major |