Last reviewed 2026-04-20 · How we verify

Estring (Estradiol)

Prevents pregnancy primarily by suppressing ovulation.

Iclevia is a combination oral contraceptive containing levonorgestrel and ethinyl estradiol indicated for pregnancy prevention in females of reproductive potential. The drug works primarily by suppressing ovulation through hormonal mechanisms. Significant contraindications exist for patients with thrombotic disease risk, cardiovascular disease, uncontrolled hypertension, certain migraine types, and hormone-sensitive cancers. Metabolic enzyme inducers may reduce contraceptive effectiveness, requiring backup contraception methods.

At a glance

Mechanism of action

Iclevia is a combination oral contraceptive containing levonorgestrel (a progestin) and ethinyl estradiol (an estrogen). The primary mechanism of action is suppression of ovulation, preventing the release of an egg from the ovary. The hormonal components work together to inhibit the luteinizing hormone (LH) surge necessary for ovulation to occur.

Approved indications

• Acne vulgaris
• Advanced Prostatic Carcinoma
• Atrophic vaginitis
• Atrophic vulva
• Contraception
• Controlled ovarian stimulation
• Female hypogonadism syndrome
• Hormone replacement cycle in embryo transfer
• Menopausal flushing
• Metastatic Breast Carcinoma
• Metastatic Prostate Carcinoma
• Ovarian deficiency symptoms
• Postmenopausal osteoporosis
• Premenstrual dysphoric disorder
• Primary ovarian failure
• Urethral atrophy
• Vasomotor symptoms associated with menopausal disorder

Boxed warnings

• WARNING: CIGARETTE SMOKING AND SERIOUS CARDIOVASCULAR EVENTS Cigarette smoking increases the risk of serious cardiovascular events from combination oral contraceptive (COC) use. This risk increases with age, particularly in women over 35 years of age, and with the number of cigarettes smoked. For this reason, COCs, including Iclevia, are contraindicated in women who are over 35 years of age and smoke [see Contraindications (4) and Warnings and Precautions (5.1) ]. WARNING: CIGARETTE SMOKING AND

Common side effects

• Acne
• Headache
• Weight increased
• Withdrawal bleeding irregular
• Nasopharyngitis
• Vaginal candidiasis
• Cervical dysplasia
• Metrorrhagia
• Influenza
• Nausea
• Dysmenorrhoea
• Urinary tract infection

Drug interactions

• Metabolic enzyme inducers (e.g., CYP3A4 inducers)
• St. John's wort

Patents

Primary sources

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