Medroxyprogesterone

What medroxyprogesterone is used for

Medroxyprogesterone is a progestin, a synthetic form of the hormone progesterone, sold as 5mg and 10mg tablets. It is taken when periods are irregular or vaginal bleeding is abnormal, and to bring back a normal cycle in women who have had periods before but none for six months or more and who are not pregnant or going through menopause. It also stops the lining of the uterus (the endometrium) thickening too much in people who take oestrogen, which may lower the risk of cancer of the uterus. Amenorrhoea (periods that have stopped), endometrial hyperplasia, endometriosis, hormone replacement and abnormal uterine bleeding are all conditions these tablets are used for.

The days you take them

Most people take one tablet a day for part of each month rather than every day: a set number of days on, then a break, repeated month after month. Others take it daily. Whichever pattern you are on, taking the tablet at about the same time on the days it is due keeps the hormone level steady. The progestin slows the build-up of the uterine lining and shifts the uterus into the second half of a cycle's hormone pattern, so bleeding arrives on schedule instead of whenever it likes. These tablets manage the problem rather than cure it.

Side effects, and the signs that need urgent help

Tender breasts or fluid from the nipples, a change in how heavy or regular periods are, spotting, acne, extra facial hair, thinning scalp hair, trouble sleeping or daytime drowsiness, an upset stomach and weight change are the effects most often reported. A blood clot is the serious risk: pain, swelling, warmth or redness in one leg only, sudden sharp chest pain, breathlessness, a fast heartbeat or coughing up blood all need urgent treatment. So do stroke warning signs — weakness or numbness in an arm or leg, slow or slurred speech, dizziness or fainting — and any sudden change in vision or loss of it. Yellowing of the skin or eyes, hives, a rash, itching, or swelling of the face, throat, hands or ankles should be checked the same day. Depression and missed periods have also been reported.

Medicines that lower its effect

Some medicines speed up the liver enzymes that break medroxyprogesterone down — rifampicin, rifabutin, carbamazepine, phenytoin and St John's wort among them. While you take one of those, less progestin stays in the body and the tablets may work less well.

The three medroxyprogesterone tablets sold here

Medroxyprogesterone tablets, Provera and Cycrin hold the same medicine in the same two strengths, 5mg and 10mg. Provera and Cycrin are brand names; the third is sold under the ingredient name. Between them they cover the whole range of uses above, and all three sit in Women's Health. Choose the strength and pack size that suits your course.