Levlen

Two hormones that stop an egg being released

Levlen is a combined pill, so each tablet carries an oestrogen (ethinyl estradiol 0.03mg) and a progestin (levonorgestrel 0.15mg). The pair quiets the hormone signals that tell an ovary to release an egg, and levonorgestrel also thickens the mucus at the cervix so sperm find it harder to get through. That protection depends on the hormone levels staying up, which is why a tablet is needed every day.

A pack of 63, 126, 189 or 252 tablets is three, six, nine or twelve cycles of 21.

Fitting a tablet into the day

Most people attach the tablet to something that already happens daily, such as breakfast or brushing their teeth at night, which keeps doses roughly 24 hours apart. You take one a day for 21 days, then have seven days without while the withdrawal bleed comes. If the pill makes you queasy, taking it with food or at bedtime often helps.

If a tablet comes back up within a few hours of taking it, or severe diarrhoea follows, the dose may never have been absorbed: take another tablet and use condoms for the next seven days. A tablet missed by more than 24 hours needs taking as soon as you can, with condoms for the following week. Protection begins at once when the first tablet is taken on day one of a period; on any other day, the first seven days need a backup method.

What you might notice

The first two or three packs are usually the noisiest: nausea, headaches, tender breasts, low mood and spotting between periods are common and often settle as the body adjusts. Bleeding in the tablet-free week tends to be lighter and less painful than a natural period.

Blood clots, heart attacks and strokes are rare risks of combined pills, and they are higher in smokers over 35. Sudden breathlessness, chest pain, a severe headache out of nowhere, vision changes, or weakness or numbness in an arm or leg need urgent treatment.

Medicines and herbs that lower protection

Levlen is less reliable alongside enzyme inducers, medicines and herbs that make the liver clear its hormones faster. That covers rifampicin and rifabutin, carbamazepine, phenytoin, griseofulvin, higher-dose topiramate and St John's wort, and the lowered cover lasts through the course plus 28 days. Everyday antibiotics like amoxicillin, doxycycline or metronidazole make no difference.

Levlen or Alesse?

Both are combined pills built on ethinyl estradiol and levonorgestrel, so the difference between them comes down to brand, strengths and pack size. Levlen keeps to one 0.03/0.15mg tablet; Alesse is the other ethinyl estradiol and levonorgestrel tablet sold here, with its own strengths.