CYCLOGEST 400MG PESSARIES

Indications

• Amenorrhea
• Endometrial hyperplasia
• Luteal phase deficiency
• Recurrent miscarriage
• Hormone replacement therapy
• Prevention of preterm birth in women with a history of spontaneous preterm birth

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations.

Adults: Refer to the BNF for specific dosing guidelines based on the condition being treated.

Mechanism of action

Progesterone exerts its effects primarily by binding to progesterone receptors in target tissues. This interaction leads to the regulation of gene expression, affecting the growth and differentiation of the endometrium, promoting the maintenance of pregnancy, and modulating the immune response during gestation.

Pharmacodynamics

After administration, progesterone induces secretory changes in the endometrium, making it conducive to implantation and maintaining pregnancy. It also inhibits uterine contractions, thus preventing premature labor. Additionally, progesterone influences the mammary glands, preparing them for milk production.

Pharmacokinetics

Progesterone is rapidly absorbed when administered orally or intramuscularly, with peak plasma concentrations occurring within a few hours. It is extensively metabolized in the liver, primarily through hydroxylation and conjugation, and has a half-life ranging from about 5 to 20 minutes. The metabolites are excreted in urine. The bioavailability of oral progesterone is low due to first-pass metabolism; hence, alternative routes such as intramuscular injection or vaginal administration may be preferable for certain indications.

Contra-indications

• Known hypersensitivity to progesterone or any of the excipients
• History of thromboembolic disorders
• Current or past history of breast cancer
• Undiagnosed vaginal bleeding
• Severe liver disease
• Porphyria

Adverse effects

• Headache
• Mood changes
• Breast tenderness
• Nausea
• Fatigue
• Dizziness
• Abdominal pain
• Menstrual irregularities
• Weight gain
• Fluid retention

Interactions

• Anticoagulants - may affect their metabolism
• CYP450 enzyme inducers (e.g., rifampicin, carbamazepine) - may decrease progesterone levels
• CYP450 enzyme inhibitors (e.g., ketoconazole) - may increase progesterone levels
• Hormonal contraceptives - may have additive effects

Precautions

• Use with caution in patients with a history of depression
• Monitor closely in patients with cardiovascular disease
• May affect glucose tolerance; use with caution in diabetic patients
• Assess the risk of thromboembolic events prior to initiation
• Evaluate the risk of hormone-sensitive tumors

Pregnancy

Progesterone is classified as a Category B medication. It is generally considered safe for use during pregnancy, especially in cases of luteal phase defects or recurrent miscarriage.

Breast-feeding

Progesterone is excreted in breast milk. While it is generally considered safe, caution is advised and monitoring of the infant for any adverse effects is recommended.

Storage

Store at room temperature, away from light and moisture. Keep out of reach of children.

Formulations

• Oral capsules
• Injectable solutions
• Topical creams