Dianette tablets contain two active ingredients, cyproterone acetate and ethinylestradiol. This combination of medicines is also known as co-cyprindiol. (NB. Co-cyprindiol tablets are also available without a brand name, ie as the generic medicine.)
Cyproterone acetate is a type of medicine called an anti-androgen. Androgens are male hormones and are produced by women as well as men. They are responsible for stimulating the growth of the skin, including the sebaceous glands that produce oil (sebum), and the hair that grows from the skin. However, if your body produces too much androgen, or if your skin is particularly sensitive to the effects of androgens, the sebaceous glands may produce too much sebum. This can cause the sebaceous glands to become blocked, resulting in infection, inflammation and acne spots. The androgens may also cause excessive growth of the hair on the face and body - a condition known as hirsutism. Both these problems are common in women with polycystic ovary syndrome (PCOS).
Cyproterone acetate is used to prevent these actions of the androgens. It works by blocking the receptors in the body that the androgens normally work on. This means that the androgens can no longer affect the skin or the hair and acne and hirsutism can improve. Cyproterone acetate also decreases the production of androgens by the ovaries, so that there are less of these male hormones circulating.
You should notice that your skin becomes less greasy within a few weeks of treatment with this medicine, but it may take a few months of treatment before you see a definite improvement in your acne or excessive hair growth.
This medicine is also an effective combined oral contraceptive pill. Cyproterone acetate is a progestogen derivative, and the other ingredient, ethinylestradiol, is a synthetic version of the naturally-occurring female hormone, oestrogen. The medicine works as a contraceptive by preventing the ripening and release of eggs from the ovaries, as well as increasing the thickness of the cervical mucus, which makes it more difficult for sperm to cross from the vagina into the womb. It also changes the lining of the womb so that it is less suitable for any fertilised eggs to successfully implant in.
Each tablet has the same dose of hormones in it. One tablet is taken every day for 21 days and you then have a seven day break from pill-taking. During your seven day break, the levels of the hormones in your blood drop, which results in a withdrawal bleed that is similar to your normal period. You start the next pack after the seven pill-free days are up, even if you are still bleeding.
The tablets come in a calendar pack marked with days of the week to help you remember to take a pill every day for three weeks, followed by a week off. You will still be protected against pregnancy in your pill-free week, provided you took all the pills correctly, you start the next packet on time and nothing else happened that could make the pill less effective (eg sickness, diarrhoea, or taking certain other medicines - see below).
This medicine is as effective a contraceptive as any other combined hormonal contraceptive, but it should not be used solely for this purpose. It is used to treat severe acne and hirsutism in women and has the advantage of also providing contraception. This means you do not need to use any other method of contraception while you are using this medicine, unless you miss a pill, have a stomach upset, or are prescribed certain other medicines as well. See below for more information about all of these scenarios.
It can take a few months of treatment before your acne or hirsutism has completely cleared up and it is recommended that you stop using this medicine three to four months after your skin has got better, rather than use it continuously just for contraception. If your acne or hirsutism flares up again, you can take repeat courses.
You should try and take your pill at the same time every day to help you remember to take it. This is particularly important if you are relying on this medicine for contraception.
If you forget to take ONE pill, or start your new pack one day late, you should take the pill you missed as soon as possible, then continue taking the rest of the pack as normal. You will still be protected against pregnancy and you don't need to use extra contraception.
If you forget to take TWO or more pills, or start your new pack two or more days late, you won't be protected against pregnancy. You should take the last pill you missed as soon as possible, forget the other missed ones and then continue to take your pills, one every day, as normal. You should either not have sex, or use an extra barrier method of contraception, eg condoms, for the next seven days.
If you had unprotected sex in the seven days before you missed pills, you may need emergency contraception (the morning after pill). Ask for medical advice.
If there are fewer than seven pills left in your pack after your last missed pill, you should finish the pack and then start a new pack straight away without a break. This means skipping your pill-free week.
If there are seven or more pills left in your pack after your last missed pill, you should finish the pack and have your seven day break as usual before starting the next pack.
If you are confused about any of this, you can get individual advice for your circumstances from your doctor, pharmacist, local family planning clinic, or by calling the fpa helpline on 0845 122 8690.
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here does not mean that all people using this medicine will experience that or any side effect.
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer. For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start taking this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while using this one, to ensure that the combination is safe.
You should not take any other hormonal contraception while taking this medicine, as this will expose you to excessive doses of hormones and is not necessary for effective contraception. (However, also see below.)
The following medicines speed up the breakdown of the hormones in this medicine by the liver, which makes it less effective as an acne and hirsutism treatment and at preventing pregnancy:
If you regularly take any of these medicines, Dianette is not recommended for you, because these medicines are likely to make it ineffective.
If you are prescribed a short course (up to two months) of any of the above medicines they will also make Dianette less effective. Your doctor may recommend that you temporarily stop using this medicine and use a different form of contraception to prevent pregnancy. However, if you want to keep taking this pill, your doctor may advise you to take three packets back to back without a break, then have only a four day pill-free break, then take three packets back to back again. (This is called tricycling and is unlicensed.) You will also need to use an additional method of contraception (eg condoms), while you are doing this, for as long as you take the liver-affecting medicine and for at least four weeks after stopping it. Alternatively, your doctor could prescribe an additional pill to take in combination with this one, or ask you to take two pills per day. (This is also unlicensed.) Discuss your options with your doctor.
If you are prescribed rifampicin or rifabutin, an alternative method of contraception will always be recommended, because these two antibiotics make the pill so ineffective.
In the past, if you were prescribed an antibiotic other than rifampicin or rifabutin (eg amoxicillin, erythromycin, doxycycline) while taking the pill, the advice used to be that you use an extra method of contraception (eg condoms) while you were taking the antibiotic and for seven days after finishing the course. However, this advice has now changed. You no longer need to use an extra method of contraception with the pill while you take a course of antibiotics. This change in advice comes because to date there is no evidence to prove that antibiotics (other than rifampicin or rifabutin) affect the pill. This is the latest guidance from the Faculty of Sexual & Reproductive Healthcare. However, if you experience vomiting or diarrhoea as a result of taking an antibiotic you should follow the instructions for vomiting and diarrhoea described in the warning section above.
The weight loss medicine orlistat (bought without a prescription as Alli and prescribed as Xenical) can cause severe diarrhoea. If you take either of these medicines while taking Dianette and get diarrhoea that lasts for more than 24 hours, you should follow the instructions for missed pills described above.
The pill may antagonise the blood sugar lowering effect of medicines for diabetes. If you have diabetes you should monitor your blood sugar and seek advice from your doctor or pharmacist if your blood sugar control seems to be altered after starting this contraceptive.
The pill may antagonise the effect of medicines used to lower high blood pressure. Your blood pressure will usually be checked periodically while you are taking the pill, but this is particularly important if you are also taking medicines for high blood pressure.
The pill may also antagonise the fluid-losing effect of diuretic medicines.
If you have an underactive thyroid gland (hypothyroidism) you may need an increased dose of your thyroid hormones while taking the pill. Your thyroid hormone levels should be regularly checked.
The pill may decrease the amount of the antiepileptic medicine lamotrigine in the blood. As this could increase the risk of seizures coming back or getting worse, the pill may not be recommended for women who take lamotrigine on its own for epilepsy.
The pill may increase the blood levels of the following medicines and this could possibly increase the risk of their side effects:
Co-cyprindiol tablets are also available without a brand name, ie as the generic medicine.