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Common uses
Norimin is a birth control pill commonly known as a "Combined Oral Contraceptive", that contains both an oestrogen (ethinyloestradiol) and progestogen (norethisterone) hormone.
Oral contraceptives belonging to this group produce their birth control (or contraceptive) effect by preventing ovulation (or the release of an egg from the ovary) during each menstrual cycle. Combined Oral Contraceptives also cause changes to the mucus of the cervix and the lining of the womb which contribute to the contraceptive action.
Norimin tablets contain two active ingredients, ethinylestradiol and norethisterone. These are synthetic versions of the naturally occurring female sex hormones, oestrogen and progesterone. Ethinylestradiol (previously spelt ethinyloestradiol in the UK) is a synthetic version of oestrogen and norethisterone is a synthetic form of progesterone.
Combined oral contraceptives like Norimin work by over-riding the normal menstrual cycle. In a woman's normal menstrual cycle, levels of the sex hormones change throughout each month. The hormones cause an egg to be released from the ovaries (ovulation) and prepare the lining of the womb for a possible pregnancy. At the end of each cycle, if the egg has not been fertilised the levels of the hormones fall, causing the womb lining to be shed as a monthly period.
The daily dose of hormones taken in the pill work mainly by tricking your body into thinking that ovulation has already happened. This prevents an egg from ripening and being released from the ovaries each month.
The hormones also increase the thickness of the natural mucus at the neck of the womb, which makes it more difficult for sperm to cross from the vagina into the womb and reach an egg. They also change the quality of the womb lining (endometrium), making it less likely that a fertilised egg can implant there.
Norimin is a monophasic pill. This means that 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 calender 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).
The contraceptive pill results in lighter, less painful and more regular menstrual bleeding. This means it is sometimes prescribed for women who have problems with particularly heavy, painful or irregular periods.
Before using
Before you start to take it you must tell your doctor if:
you are a heavy smoker (15 or more cigarettes per day), especially if you are aged over 35 years. Oral contraceptives increase your risk of having a stroke or heart attack. Smoking while taking oral contraceptives further increases this risk.
you have gallbladder disease.
you have kidney or heart disease.
you have high blood pressure.
you have high cholesterol.
you have diabetes.
you have epilepsy.
you have asthma.
you have migraine
you have or have had depression.
you are breastfeeding.
Small amounts of oral contraceptives
have been found in breast milk.
you wear contact lenses.
you are lactose intolerant. This medicine contains lactose.
Directions
Ideally, you should start taking this pill on day one of your menstrual cycle (the first day of your period). This will protect you from pregnancy immediately and you won't need to use any additional methods of contraception. If necessary, you can also start taking it up to day five of your cycle without needing to use additional contraception when you start. However, if you have a short menstrual cycle (with your period coming every 23 days or less), starting as late as the fifth day of your cycle may not provide you with immediate contraceptive protection. You should talk to your doctor or nurse about this and whether you need to use an additional contraceptive method for the first seven days.
You can also start taking this pill at any other time in your cycle if your doctor is reasonably sure that you are not pregnant. However, if you start taking this pill at any other time in your cycle, you won't be protected from pregnancy straight away and you will need to use additional contraception, eg condoms (or not have sex) for the first seven days of pill taking.
If you have given birth and are not breastfeeding, you can start taking this pill on day 21 after the birth. You will be protected against pregnancy immediately and do not need to use extra contraception. If you start taking it later than 21 days after giving birth, you will need to use extra contraception for the first seven days.
If you are starting this pill immediately after a miscarriage or abortion at under 24 weeks, you will protected against pregnancy immediately. If you start taking it more than seven days after the miscarriage or abortion, you should use extra contraception for the first seven days of pill taking.
Cautions
Do not use Norimin if you have unexplained vaginal bleeding. Also avoid Norimin if there is a possibility that you are pregnant.
Do not use Norimin if there is any chance that you have breast cancer or any other cancer stimulated by estrogen. You will also have to avoid Norimin if it causes an allergic reaction.
Possible side effects
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. See also the warnings above. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
Nausea and vomiting
Headache/migraine
Breast tenderness, enlargement
Weight changes
Retention of water in the body tissues (fluid retention)
Vaginal thrush (candidiasis)
Change in menstrual bleeding
Menstrual spotting or breakthrough bleeding
Depression
Skin reactions
Decreased sex drive
Rise in blood pressure
Irregular brown patches on the skin, usually of the face (chloasma)
Steepening of corneal curvature which may make contact lenses uncomfortable
Disturbance in liver function
Gallstones
Blood clots in the blood vessels (eg, DVT, pulmonary embolism, heart attack, stroke - see warnings above)
The side effects listed above may not include all of the side effects reported by the drug'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.
If you take too much
Overdosage may cause nausea. This may be followed by vaginal bleeding in some women.
Additional information
Estrogen replacement therapy increases the risk of developing cancer of the lining of the uterus. The risk increases with longer use and higher doses. Therefore, you should use Norimin (Ethinyl Estradiol and Norethindrone) for as short a time and at as low a dose as is necessary to relieve your symptoms. Report any unusual vaginal bleeding to you doctor immediately.
Drug interactions
Some medicines may interfere with the effectiveness of Norimin. These include medicines such as:
• Rifampicin for the treatment of tuberculosis.
• Antibiotics such as ampicillin, oxacillin, tetracyclines, sulfamethoxazole and trimethoprim.
• Anti-fungal agents such as griseofulvin.
• Barbiturates.
• Medicines for epilepsy such as carbamazepine and phenytoin.
• Phenylbutazone, a medicine used to relieve symptoms of inflammation, including arthritis.
• St John's wort, an ingredient found in medicines you can purchase without a prescription from a pharmacy, supermarket or health food shop.
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