Microgynon 28 (Ethinylestradiol, Levonorgestrel | Lactose Monohydrate)

• Microgynon 28, a combined oral contraceptive, is indicated for the following clinical purposes:
• Prevention of pregnancy: provides reliable contraception for women seeking to avoid unintended pregnancy.
• Regulation of menstrual cycles: helps establish a predictable menstrual pattern and reduce cycle irregularities.
• Management of menstrual‑related symptoms: can alleviate dysmenorrhea and premenstrual discomfort associated with hormonal fluctuations.
• Treatment of acne associated with androgen excess: may improve skin condition by reducing circulating androgen levels.

• Ethinylestradiol and levonorgestrel act synergistically to suppress the hypothalamic‑pituitary‑ovarian axis. Ethinylestradiol supplies estrogenic activity that stabilises the endometrium, while levonorgestrel, a progestogen, blocks the mid‑cycle luteinising hormone surge, preventing ovulation. The progestogenic component also thickens cervical mucus and induces endometrial changes that are unfavourable for implantation, thereby achieving contraceptive efficacy.

Microgynon 28 may be associated with a range of adverse reactions, which are categorised by frequency and severity.

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Headache: tension‑type or migraine‑like pain.
• Breast tenderness: temporary swelling or discomfort.
• Weight gain: slight increase in body weight.
• Spotting or breakthrough bleeding: irregular light bleeding between periods.

Serious or Rare Side Effects

• Venous thromboembolism: deep‑vein thrombosis or pulmonary embolism.
• Arterial thrombosis: stroke or myocardial infarction.
• Severe hypertension: sudden elevation of blood pressure.
• Liver dysfunction: jaundice or abnormal liver enzymes.
• Allergic reactions: rash, swelling, or anaphylaxis.

• Before prescribing Microgynon 28, clinicians should consider the following precautions and warnings.
• Contraindications: avoid use in women with a history of thromboembolic disorders, estrogen‑dependent tumours, or active liver disease.
• Smoking: do not prescribe to women over 35 who smoke, due to increased cardiovascular risk.
• Migraine with aura: contraindicated because of heightened stroke risk.
• Medication adherence: missed tablets can reduce efficacy; advise consistent daily intake.
• Pregnancy and lactation: contraindicated during pregnancy; breastfeeding women should consult a physician.
• Store at ambient temperature: keep below 25 °C, in the original packaging, protected from moisture and light.

Microgynon 28 can interact with other medicines, altering its effectiveness or safety profile.

Major Interactions (Avoid)

• Antiepileptic enzyme inducers (e.g., carbamazepine, phenytoin, rifampicin): markedly reduce contraceptive efficacy.
• Certain antibiotics (e.g., griseofulvin): may decrease hormone levels, risking breakthrough bleeding.
• Antiretroviral protease inhibitors (e.g., ritonavir): can increase hormone concentrations, raising thrombosis risk.
• High‑dose SSRIs (e.g., fluoxetine): may increase plasma levels of ethinylestradiol.

Moderate Interactions (Monitor Closely)

• St. John’s wort: may modestly reduce contraceptive effect; advise backup method.
• Diuretics (e.g., thiazides): can increase risk of hypertension; monitor blood pressure.
• Antifungal azoles (e.g., ketoconazole): may increase hormone levels; watch for signs of estrogen excess.