Levosert One (Levonorgestrel)

Levonorgestrel delivered via Levosert One acts on the reproductive system to provide hormonal contraception.

• Contraception: Provides long‑term prevention of pregnancy by thickening cervical mucus, inhibiting endometrial growth and suppressing ovulation.
• Treatment of heavy menstrual bleeding: Reduces menstrual blood loss and improves bleeding patterns in women with dysfunctional uterine bleeding.
• Management of dysmenorrhea: Alleviates painful menstrual cramps through local progestogenic effects on the endometrium.

• Levonorgestrel released from the intrauterine system binds to progesterone receptors in the cervical epithelium and endometrium. This action thickens cervical mucus, creates a hostile environment for sperm, suppresses endometrial proliferation, and may inhibit ovulation, collectively preventing fertilisation and implantation. The device provides a steady low‑dose release of about 20 µg per day over up to five years, maintaining local hormone concentrations sufficient for contraceptive effect while minimising systemic exposure.

Levosert One may be associated with a range of adverse reactions, which are generally classified by frequency and severity.

Common Side Effects

• Irregular vaginal bleeding or spotting
• Amenorrhea (absence of periods)
• Pelvic cramping
• Breast tenderness

Serious or Rare Side Effects

• Uterine perforation during insertion
• Device expulsion or displacement
• Pelvic inflammatory disease or infection
• Ectopic pregnancy if contraception fails

Prior to insertion of Levosert One, clinicians should observe several precautionary measures to ensure safety and effectiveness.

• Confirm non‑pregnancy: Verify the patient is not pregnant before device placement.
• Assess uterine anatomy: Evaluate for fibroids, septa, or other abnormalities that may impede insertion.
• Screen for active infection: Defer insertion in the presence of pelvic inflammatory disease or genital infection.
• Counsel on bleeding changes: Inform patients that irregular bleeding is common during the first months.
• Review medication history: Identify drugs that may reduce contraceptive efficacy.
• Store at room temperature: Keep the device in its original packaging, protect from moisture and direct sunlight.

Levonorgestrel released from an intrauterine system can interact with other medicines, affecting its contraceptive reliability.

Major Interactions (Avoid)

• Enzyme‑inducing anticonvulsants (e.g., carbamazepine, phenytoin, phenobarbital): may markedly reduce levonorgestrel levels.
• Rifampin or rifabutin: potent inducers that can compromise contraceptive effectiveness.
• Protease inhibitor antiretrovirals (e.g., ritonavir): may alter hormone metabolism and reduce efficacy.

Moderate Interactions (Monitor Closely)

• Antifungal azoles (e.g., ketoconazole, itraconazole): may increase levonorgestrel concentrations.
• Herbal St John’s wort: may modestly decrease hormone levels.
• Estrogen‑containing hormone therapy: may affect bleeding patterns and require monitoring.
• Certain antibiotics (e.g., griseofulvin): may have a modest impact on hormone levels.