Mpa (Medroxyprogesterone Acetate)

Medroxyprogesterone acetate is a synthetic progestogen used in several hormonal pathways and conditions.

• Menstrual disorders: regulates irregular bleeding and alleviates dysmenorrhea.
• Endometriosis: reduces ectopic endometrial tissue activity and associated pain.
• Hormone replacement therapy: provides progesterone support in post‑menopausal regimens.
• Contraception: suppresses ovulation and alters the endometrium to prevent pregnancy.
• Premenopausal symptoms: mitigates hormonal fluctuations causing mood and physical symptoms.

• Medroxyprogesterone acetate binds to intracellular progesterone receptors, activating them to inhibit gonadotropin‑releasing hormone secretion. This suppresses luteinizing hormone and follicle‑stimulating hormone release, preventing ovulation. In target tissues, it induces secretory changes in the endometrium, stabilizes the uterine lining, and exerts anti‑estrogenic effects, thereby providing contraceptive, therapeutic, and symptom‑control actions.

Adverse reactions may vary in frequency and severity.

Common Side Effects

• Weight gain: increased appetite or fluid retention.
• Headache: mild to moderate intensity.
• Nausea: occasional stomach upset.
• Breast tenderness: discomfort or swelling.
• Mood changes: irritability or depressive feelings.
• Menstrual irregularities: spotting or breakthrough bleeding.

Serious or Rare Side Effects

• Thromboembolic events: deep vein thrombosis or pulmonary embolism.
• Severe allergic reaction: rash, swelling, or anaphylaxis.
• Liver dysfunction: jaundice or elevated enzymes.
• Depression or suicidal thoughts: significant mood alteration.
• Adrenal suppression: signs of cortisol deficiency.
• Unexplained vaginal bleeding: may indicate underlying pathology.

Before initiating therapy, consider the following safety measures.

• Assess thrombotic risk: evaluate history of clotting disorders.
• Monitor liver function: perform baseline and periodic liver enzyme tests.
• Evaluate hormone‑sensitive cancers: avoid use in active breast or uterine cancer.
• Avoid use in pregnancy unless clearly indicated: discuss risks with prescriber.
• Review concomitant medications: check for potential interactions.
• Store at ambient temperature: keep in the original pack, protect from moisture and direct sunlight.

Medroxyprogesterone acetate can interact with several drug classes.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole): may increase plasma levels.
• Enzyme inducers (e.g., rifampin, carbamazepine): may reduce effectiveness.
• Anticoagulants (e.g., warfarin): may enhance bleeding risk.
• Antiretrovirals (e.g., efavirenz): may alter hormonal activity.

Moderate Interactions (Monitor Closely)

• Anticonvulsants (e.g., phenytoin): may modestly lower drug exposure.
• Glucocorticoids: combined effect on adrenal axis.
• Herbal supplements (e.g., St. John’s wort): may affect metabolism.
• Other hormonal contraceptives: assess additive effects on clot risk.
• Antifungal agents (e.g., fluconazole): may increase serum concentrations.