Mercilon 28 (Desogestrel, Ethinylestradiol | Lactose Monohydrate)

Mercilon 28 is a combined hormonal contraceptive used within the family planning and menstrual regulation pathway.

• Contraception: prevents pregnancy in women of reproductive age by inhibiting ovulation.
• Menstrual cycle regulation: helps achieve more predictable monthly periods.
• Dysmenorrhea management: reduces menstrual pain associated with ovulatory cycles.

• Desogestrel and ethinylestradiol act together to suppress the hypothalamic‑pituitary‑gonadal axis, inhibiting the mid‑cycle surge of luteinising hormone (LH) and follicle‑stimulating hormone (FSH). This prevents follicular development and ovulation. The estrogen component stabilises the endometrium, while both hormones thicken cervical mucus, creating a hostile environment for sperm penetration.

Common Side Effects

• Nausea: mild to moderate stomach upset, especially during the first cycles.
• Breast tenderness: temporary swelling or discomfort of the breasts.
• Headache: mild to moderate tension‑type headaches.
• Spotting or breakthrough bleeding: irregular light bleeding between periods.
• Mood changes: mild fluctuations in mood or irritability.

Serious or Rare Side Effects

• Venous thromboembolism: deep vein thrombosis or pulmonary embolism, requiring immediate medical attention.
• Arterial thrombosis: stroke or myocardial infarction, especially in high‑risk individuals.
• Severe hypertension: sudden increase in blood pressure that may lead to organ damage.
• Hepatic adenoma: rare benign liver tumor.
• Anaphylaxis: severe allergic reaction with rash, swelling, and breathing difficulty.

Before prescribing Mercilon 28, clinicians should evaluate individual risk factors and counsel patients on safe use.

• Assess thrombotic risk: avoid in women with a history of clotting disorders or recent surgery.
• Screen for hypertension: monitor blood pressure regularly during therapy.
• Avoid smoking: especially in women over 35 years of age.
• Evaluate liver function: contraindicated in severe hepatic impairment.
• Pregnancy category X: do not use during pregnancy; advise effective contraception.
• Store at ambient temperature: keep below 25°C in the original packaging, protect from moisture.

Mercilon 28 may interact with other medicines that affect hormone metabolism or clotting risk.

Major Interactions (Avoid)

• Antiepileptic enzyme inducers (e.g., carbamazepine, phenytoin): markedly reduce contraceptive efficacy.
• Rifampin: decreases plasma hormone levels, increasing risk of unintended pregnancy.
• St. John's wort: may lower contraceptive effectiveness.

Moderate Interactions (Monitor Closely)

• Antibiotics such as tetracycline: may slightly diminish hormonal protection.
• Antifungals (e.g., fluconazole): can increase estrogen levels, raising side‑effect potential.
• Selective serotonin reuptake inhibitors (SSRIs): may increase bleeding tendency when combined with hormonal therapy.