Progesterone capsules are a form of hormone therapy used to supplement or replace natural progesterone in individuals who are deficient or have irregular hormone levels. Commonly prescribed for menstrual irregularities, infertility, hormone replacement therapy (HRT), and to support early pregnancy in some cases, these capsules help maintain the hormonal balance essential for reproductive and overall health. Available in both natural and synthetic forms, they are often used in combination with estrogen.

Progesterone exerts its effects by binding to specific progesterone receptors in target tissues, such as the uterus, breasts, and brain. It transforms the endometrial lining from a proliferative to a secretory state, preparing it for implantation of a fertilized egg. Additionally, it reduces uterine contractions, modulates immune responses during pregnancy, and affects the hypothalamic-pituitary axis to inhibit the release of luteinizing hormone (LH), thereby regulating ovulation.

Progesterone capsules should not be used in individuals with a history of hormone-sensitive cancers (such as breast or uterine cancer), active liver disease, unexplained vaginal bleeding, or thromboembolic disorders. Caution is advised in patients with cardiovascular disease, migraines, asthma, epilepsy, or depression. Long-term use should be regularly reviewed by a healthcare provider to assess risk-benefit balance.

Progesterone may interact with several medications, altering its effectiveness or increasing the risk of adverse effects. Drugs such as rifampin, carbamazepine, and phenytoin can reduce progesterone levels by increasing its metabolism. Concurrent use with other hormone therapies, especially estrogen, should be carefully managed to avoid hormonal imbalance.

Common side effects include dizziness, fatigue, bloating, breast tenderness, mood swings, and headache. Some users may experience nausea, breakthrough bleeding, or changes in menstrual patterns. Rare but serious adverse effects can include thromboembolic events, jaundice, and allergic reactions. Any unusual symptoms should be reported promptly to a healthcare provider.

Progesterone is often prescribed during early pregnancy to support the uterine lining and reduce the risk of miscarriage in certain cases. When used under medical supervision, it is considered generally safe in pregnancy. During breastfeeding, progesterone may pass into breast milk in small amounts; however, no significant adverse effects have been reported in nursing infants. Nonetheless, usage should be discussed with a healthcare provider.

Store this medication at 68°F to 77°F (20°C to 25°C) and away from heat, moisture and light. Keep all medicine out of the reach of children. Throw away any unused medicine after the beyond-use date. Do not flush unused medications or pour down a sink or drain.

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