Combined oral contraceptive
Medication
oestrogen + progestin
hormonal
Not medical advice. Check with your doctor or pharmacist before you start, stop or change the timing of anything you take.
How to use
What it’s for
Preventing pregnancy — NHS: >99% effective used correctly
When to take
One tablet at the SAMe time daily · 21-day or everyday packs
Take with
US label: without regard to meals, SAMe time each day
Pros & cons
Pros
- NHS: >99% effective used correctly, 91% in practice
- NHS: periods often lighter, more regular, less painful
- NHS: may ease pms, endometriosis and severe acne
Cons
- US label: boxed — not for smokers over 35
- NHS: blood clot in up to 1 in 1,000 users
- NHS: breakthrough bleeding common in early months
Sources
- HSA — Listing of Registered Therapeutic Products (data.gov.sg open dataset, 5,511 rows, full CSV pulled once via the datastore_search API and filtered locally) · read 2026-08-27
what it says
“Forensicclassification = 'Prescription Only' for every combined oral contraceptive row: SIN12334P YASMIN, SIN13584P YAZ, SIN04834P MICROGYNON 30, SIN06136P MERCILON, SIN04784P DIANE-35, SIN12117P ESTELLE-35, SIN14855P DROSPERA, SIN14996P GVEZA, SIN14995P JASTINDA, SIN14894P LIZA”
- NHS — Combined pill: what is it (page dateModified 15 Apr 2025) · read 2026-08-27
what it says
“The combined contraceptive pill (also called the pill) is a type of hormonal contraception. It stops your ovaries releasing an egg each month.”
- NHS — Combined pill: how to take it · read 2026-08-27
what it says
“There are 2 main ways to take the combined pill … You take the everyday (ED) pill every day … You take the 21-day pill for 21 days, then have a break (not taking a pill) for 7 days.”
- NHS — Combined pill: effectiveness · read 2026-08-27
what it says
“You need to take the combined pill at the same time every day for it to work properly. When used correctly all the time, the pill is more than 99% effective. If not used correctly, it's 91% effective”
- NHS — Combined pill: who can take it · read 2026-08-27
what it says
“You may not be able to take it if you're living with obesity, or you're aged 35 or over and you smoke … blood clots … narrowed or blocked arteries, or a stroke … migraines with warning signs called aura”
- NHS — Combined pill: use for acne and heavy or painful periods · read 2026-08-27
what it says
“Taking the combined pill usually makes your periods regular, lighter and less painful. The pill may also help the symptoms of: premenstrual syndrome (PMS) · endometriosis … severe acne”
- NHS — Combined pill: after birth and while breastfeeding · read 2026-08-27
what it says
“If you're breastfeeding, you should wait 6 weeks after giving birth before you start taking the pill. You'll need to use a different method of contraception, such as condoms, until then”
- NHS — Combined pill: side effects · read 2026-08-27
what it says
“Bleeding between periods (breakthrough bleeding) or changes to your periods are common in the first few months. Taking the pill can cause high blood pressure in a small number of people.”
- NHS — Combined pill: risks and complications · read 2026-08-27
what it says
“The risk of getting a blood clot is very small and affects up to 1 in 1,000 people using combined hormonal contraception like the pill … can slightly increase your risk of getting: breast cancer · cervical cancer”
- NHS — Combined pill: medicines and herbal remedies that affect it · read 2026-08-27
what it says
“Some medicines and herbal remedies can affect how the combined pill works … before taking the pill if you take medicine to treat TB, epilepsy or HIV … griseofulvin, lamotrigine (a mood stabiliser), or St John's wort”
- NHS — Combined pill: where to get it (UK supply route, for contrast with Singapore) · read 2026-08-27
what it says
“You can get the combined pill free on the NHS from sexual health clinics, GP surgeries and young people's services … A pharmacist may be able to supply the combined pill for free without a prescription.”
- FDA DailyMed — Kurvelo (levonorgestrel and ethinyl estradiol tablets USP, 0.15 mg/30 mcg), Lupin Pharmaceuticals, SPL v12, effective 20 May 2026 · read 2026-08-27
what it says
“Kurvelo is indicated for use by females of reproductive potential to prevent pregnancy … Counsel patients to take one tablet daily by mouth at the same time every day.”
- FDA DailyMed — Kurvelo: Dosage and Administration, Table 3 · read 2026-08-27
what it says
“Take first tablet without regard to meals on the first day of menses · Take subsequent tablets once daily at the same time each day · Begin each subsequent pack on the same day of the week”
- FDA DailyMed — Kurvelo prescribing information: boxed warning · read 2026-08-27
what it says
“WARNING: CIGARETTE SMOKING AND SERIOUS CARDIOVASCULAR EVENTS — Cigarette smoking increases the risk of serious cardiovascular events from combination oral contraceptive (COC) use … COCs, including Kurvelo, are contraindicated in women who are over 35 years of age and smoke”
- FDA DailyMed — Kurvelo prescribing information: precautions on absorption · read 2026-08-27
what it says
“Diarrhea and/or vomiting may reduce hormone absorption (see DOSAGE AND ADMINISTRATION).”
- FDA DailyMed — Levonorgestrel and ethinyl estradiol tablets (extended-cycle, 91-day), Lupin Pharmaceuticals, SPL v19, effective 31 Aug 2026 · read 2026-08-27
what it says
“Take one tablet daily by mouth at the same time every day for 91 days … Patients should take one tablet daily by mouth at the same time every day.”
Updated 2026-08-29. Every line above traces to a numbered source. Kozen-X is not a medical device and does not give medical advice. It lists what published sources have written down — nothing more. A pair not listed is unrecorded, not cleared. Before you start, stop or re-time anything, talk to your doctor or pharmacist.