Lencya (Ulipristal Acetate)

Lencya (ulipristal acetate) is used as an emergency contraceptive that modulates progesterone receptors to prevent ovulation.

• Emergency contraception: prevents pregnancy after unprotected sexual intercourse when taken within five days.
• Post‑coital contraception: provides a rapid, non‑hormonal option for women seeking immediate pregnancy prevention.
• Contraceptive failure management: effective after missed pills or condom breakage to reduce risk of unintended pregnancy.

• Ulipristal acetate binds to progesterone receptors in the hypothalamic‑pituitary‑ovarian axis, acting as an antagonist or modulator. By occupying the receptor, it blocks the progesterone‑driven luteinizing hormone surge, thereby inhibiting or delaying follicular rupture and ovulation. This effect can occur even after the pre‑ovulatory surge has begun, extending the window of efficacy compared with estrogen‑progestin combinations in women of reproductive age.

Ulipristal acetate may cause a range of adverse reactions, most of which are mild and transient.

Common Side Effects

• Nausea: mild stomach upset often occurring shortly after ingestion.
• Headache: transient tension‑type headache.
• Fatigue: feeling of tiredness or reduced energy.
• Abdominal pain: mild cramping or discomfort.
• Menstrual changes: spotting or delayed onset of the next period.
• Dizziness: occasional light‑headed sensation.

Serious or Rare Side Effects

• Severe allergic reaction: rash, itching, swelling, or difficulty breathing.
• Liver injury: jaundice, dark urine, or elevated liver enzymes.
• Thromboembolic events: rare clot formation presenting as leg pain or swelling.
• Persistent amenorrhea: prolonged absence of menstrual periods beyond expected time.

When prescribing Lencya, clinicians should consider several precautionary measures to ensure safe use.

• Assess timing: confirm the product is taken within five days of unprotected intercourse.
• Review medical history: ensure no known hypersensitivity to ulipristal acetate or excipients.
• Pregnancy status: avoid use if a confirmed pregnancy is present.
• Concomitant hormonal contraception: advise that ongoing hormonal methods may be less effective immediately after use.
• Liver function: consider baseline liver assessment in patients with known hepatic disease.
• Store at ambient temperature: keep below 25 °C in the original packaging, protected from moisture and light.

Ulipristal acetate can interact with other medicines, altering its effectiveness or safety profile.

Major Interactions (Avoid)

• CYP3A inducers: drugs such as rifampicin, carbamazepine, or St John’s wort may markedly reduce ulipristal levels.
• Hormonal contraceptives: concurrent use may diminish the efficacy of combined oral contraceptives.

Moderate Interactions (Monitor Closely)

• CYP3A inhibitors: strong inhibitors like ketoconazole can increase ulipristal exposure.
• Anticonvulsants: enzyme‑inducing agents may require monitoring of efficacy.
• Herbal supplements: certain botanicals affecting CYP enzymes may alter drug levels.