Nomegestrol Arrow (Nomegestrol Acetate)

Nomegestrol Arrow is a synthetic progestin that acts on the reproductive hormone pathway to prevent pregnancy and treat hormone‑related conditions.

• Contraception: Provides progestin‑only oral contraception by suppressing ovulation and altering cervical mucus.
• Menstrual disorder management: Reduces irregular bleeding and alleviates dysmenorrhea.
• Hormone replacement therapy: Supplies progestogenic support in post‑menopausal hormone regimens.

• Nomegestrol acetate is a selective progesterone receptor agonist. By binding to progesterone receptors in the hypothalamus and pituitary, it inhibits the luteinizing hormone surge, thereby suppressing ovulation. In the cervix it thickens mucus, and in the endometrium it induces secretory changes that reduce the likelihood of implantation.

Nomegestrol Arrow may cause a range of adverse reactions. Patients should be aware of both common and serious possibilities.

Common Side Effects

• Headache: mild to moderate intensity.
• Nausea: occasional upset stomach.
• Breast tenderness: transient discomfort.
• Weight gain: modest increase in body weight.
• Mood changes: irritability or mood swings.
• Irregular vaginal bleeding: spotting or breakthrough bleeding.

Serious or Rare Side Effects

• Venous thromboembolism: deep vein thrombosis or pulmonary embolism.
• Severe allergic reaction: rash, swelling, or anaphylaxis.
• Liver dysfunction: jaundice or elevated liver enzymes.
• Depression: new or worsening depressive symptoms.
• Hypertension: significant rise in blood pressure.
• Ocular changes: visual disturbances or retinal vein occlusion.

Before initiating therapy, clinicians should evaluate patient history and monitor for specific risks.

• Assess cardiovascular risk: avoid in patients with a history of thromboembolic disease.
• Screen for liver disease: contraindicated in severe hepatic impairment.
• Monitor blood pressure: watch for new or worsening hypertension.
• Consider bone health: long‑term use may affect bone mineral density.
• Store at ambient temperature: keep in the original container, protect from moisture and light.

Nomegestrol Arrow can interact with several medication classes; some require avoidance while others need careful monitoring.

Major Interactions (Avoid)

• Combined hormonal contraceptives: risk of hormonal excess.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole): may increase plasma concentrations.
• Antiretroviral protease inhibitors (e.g., ritonavir): may reduce contraceptive effectiveness.

Moderate Interactions (Monitor Closely)

• Enzyme inducers (e.g., rifampin, phenytoin, carbamazepine): may lower drug levels.
• Certain antibiotics (e.g., rifampin): may diminish efficacy.
• Herbal supplements (e.g., St. John's wort): may decrease contraceptive reliability.