Progestogen-only contraceptive (POP) Pregnancy: Not indicated during pregnancy — if pregnancy occurs during treatment, further intake should be stopped. Extensive epidemiological studies have revealed neither an increased risk of birth defects in children born to women who used oral contraceptives prior to pregnancy, nor a teratogenic effect when they were taken inadvertently during early pregnancy. Breastfeeding: may be used during lactation; small amounts of etonogestrel are excreted in breast milk (an estimated 0.01-0.05 microgram/kg body weight/day may be ingested by the child). Infrequent postmarketing reports of decreased breast milk production. The development and growth of the nursing infant should be carefully observed.

Desogestrel

Brand names: Cerazette, Cerelle

Desogestrel is a progestogen used as a progestogen-only oral contraceptive ('mini-pill').

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: One 75 microgram tablet daily, taken continuously without any tablet-free interval

Route: Oral

Frequency: Once daily, every day at about the same time so that the interval between two tablets is always 24 hours; a new blister is started directly the day after the previous one

Progestogen-only contraceptive (Desogestrel 75 micrograms Tablets, UK SPC). The first tablet should be taken on the first day of menstrual bleeding; thereafter one tablet each day continuously, without taking any notice of possible bleeding. Starting on days 2-5 is allowed, but during the first cycle a barrier method is recommended for the first 7 days. Following first-trimester abortion it is recommended to start immediately (no additional contraception needed). After delivery or second-trimester abortion, treatment can be initiated before menstruation returns; if more than 21 days have elapsed, pregnancy ought to be ruled out and an additional method of contraception used for the first week. Changing from a combined hormonal contraceptive (COC, vaginal ring or transdermal patch): start preferably on the day after the last active tablet, or on the day of ring/patch removal — no additional contraceptive needed; if starting at the latest on the day following the usual tablet-/patch-/ring-free or placebo interval, an additional barrier method is recommended for the first 7 days. Changing from a progestogen-only method: may switch any day from the minipill, on the day of removal of an implant or IUS, or when the next injection would be due. Missed tablets: contraceptive protection may be reduced if more than 36 hours have elapsed between two tablets. If less than 12 hours late, take the missed tablet as soon as remembered and the next tablet at the usual time. If more than 12 hours late, use an additional method of contraception for the next 7 days; if tablets were missed in the first week and intercourse took place in the week before, the possibility of pregnancy should be considered. Gastrointestinal disturbance: if vomiting occurs within 3-4 hours after tablet-taking absorption may not be complete — apply the same advice as for a missed tablet. Before prescription a thorough case history should be taken and a gynaecological examination is recommended to exclude pregnancy; bleeding disturbances such as oligomenorrhoea and amenorrhoea should be investigated before prescription. Treatment should be stopped if pregnancy occurs. Does not protect against HIV (AIDS) or other sexually transmitted diseases. Paediatric (non per-kg, so not expressed as a mg/kg dose): 'The safety and efficacy of desogestrel in adolescents below 18 years has not yet been established. No data are available.' Verify any under-18 use against a children's formulary.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Active venous thromboembolic disorder
Presence or history of severe hepatic disease as long as liver function values have not returned to normal
Known or suspected sex-steroid sensitive malignancies
Undiagnosed vaginal bleeding
Hypersensitivity to the active substance or to any of the excipients

Side effects

Bleeding irregularity — reported in up to 50% of women; bleeding may become more frequent (20-30%), less frequent or absent (about 20%), or of longer duration
Acne
Mood altered / depressed mood, decreased libido
Breast pain
Nausea
Headache; weight increased

Interactions

Enzyme-inducing medicines — breakthrough bleeding and/or contraceptive failure may result from interactions of other drugs (enzyme inducers) with hormonal contraceptives (stated in SPC §4.8, cross-referencing §4.5; the full §4.5 interactions section was NOT captured in the fetched bundle — clinician to check the SPC §4.5 before sign-off)

Clinical monograph

How it works

It acts primarily by inhibiting ovulation, supplemented by thickening of cervical mucus to impede sperm penetration and changes to the endometrium.

Prescribing in practice

Unlike traditional progestogen-only pills, desogestrel reliably suppresses ovulation, but a missed pill beyond the permitted window still requires additional contraceptive precautions and consideration of emergency contraception.
It can be used in many women in whom oestrogen is contraindicated, including during breastfeeding.
Irregular or unpredictable bleeding is the most common reason for discontinuation and should be discussed before starting.

Monitoring

No specific laboratory monitoring is required; assess blood pressure and review contraceptive needs and any new bleeding pattern at follow-up.

Counselling the patient

Take one tablet at the same time each day without a break between packs.
If a pill is taken late beyond the allowed window, use additional precautions such as condoms as advised.
Irregular bleeding or spotting is common, especially in the early months.

Evidence & guidelines

Desogestrel-only contraception is recommended within UK guidance as an effective oestrogen-free option, including for breastfeeding women.

Reference: FSRH POP guideline; UKMEC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

T-MACS Troponin-Only Manchester ACS Decision Aid · Chest Pain

Pathways