Norimin (Norethisterone (Norethindrone) and Ethinyloestradiol 0.5mg/0.035mg) Tablets

Norimin general information

What is Norimin used for?

Norimin tablets are a low dose combined oral contraceptive pill and are used as an effective means of birth control to prevent unwanted pregnancy.  Norimin tablets contain a combination of two hormones at low doses in a single tablet.  Each pack of Norimin contains one month’s supply of tablets of which there are 21 hormone-containing tablets and 7 placebo (non-hormonal) tablets, to allow each monthly cycle to end with a withdrawal bleed.  When using Norimin for contraception, you will probably find that your periods become regular.  You may also experience lighter, less painful menstruation and an improvement in pre-menstrual symptoms, like bloating, swelling or weight gain related to fluid retention, also improvement in acne and reductions in greasiness of the skin and hair. 

How does Norimin work?

Norimin contraceptive tablets contain a combination of two hormones that work together to protect against pregnancy; ethinyloestradiol, a synthetic oestrogen, and norethisterone, a first generation synthetic progestogen that has similar action in the menstrual cycle as the natural hormone progesterone; also some androgenic and estrogenic activity.  Preparation for pregnancy depends on a complex interaction between the female sex hormones produced by the ovaries; oestrogen, which stimulates ovulation, and progesterone which prepares the endometrium (lining of the uterus) for implantation of an embryo, as well as other regulating hormones, produced by the hypothalamus in the brain and the pituitary gland.  Ethinyloestradiol and norethisterone in Norimin tablets work together by disrupting the normal menstrual cycle, preventing egg maturation and suppressing ovulation, as well as preventing development of the endometrium, so that a fertilised egg would not be able to implant and grow.  Ethinylestradiol in Norimin blocks the production of follicle stimulating hormone (FSH) by the pituitary gland which prevents development of the egg follicle.  Norethisterone in Norimin tablets works by blocking the increase in luteinising hormone (LH) levels that are needed for ovulation to occur.  Another contraceptive action of Norimin tablets is that the cervical mucus, which normally changes consistency at ovulation to become thinner, remains thick, forming a physical barrier to sperm. 

What does Norimin contain?

Norimin contraceptive tablets contain a combination of the active ingredients ethinyloestradiol (0.035mg), a synthetic oestrogen, and norethisterone (0.5mg) a synthetic progestogen that work together to protect against pregnancy.  They also contain indigo carmine lactose monohydrate magnesium stearate maize starch povidone

Norimin for contraception

Norimin contraceptive tablets contain a combination of two hormones, ethinyloestradiol, a synthetic oestrogen, and norethisterone, a synthetic progestogen, that work together to provide effective birth control by protecting against pregnancy.  Norimin contraceptive tablets work by disrupting the normal menstrual cycle, preventing egg maturation and suppressing ovulation, as well as preventing development and thickening of the endometrium (lining of the uterus) in preparation for implantation, so that a fertilised egg would not be able to implant and grow.  Norimin tablets also prevent the changes in consistency of cervical mucus, which normally become thinner at ovulation, but remains thick, forming a physical barrier to sperm.  Each pack of Norimin contains one month’s supply of tablets of which there are 21 hormone-containing tablets and 7 placebo (non-hormonal) tablets, to allow each monthly cycle to end with a withdrawal menstrual bleed, which may be light and less painful than usual, and it is important to take Norimin contraceptive tablets continually to ensure effective contraception. 

Can you get pregnant if you miss a Norimin tablet

Norimin contraceptive tablets provide effective contraception when taken correctly and have a failure rate of approximately 1% per year.  The failure rate may increase if you miss a tablet and may result in an unwanted pregnancy.  To prevent this, ensure that you take your Norimin contraceptive tablets correctly and continually.

What are the side effects of Norimin?

The most commonly reported side effects when taking Norimin tablets include nausea, vomiting, abdominal pain, vaginal inflammation (vaginitis) usually caused by candidiasis (yeast infection), dizziness, mood changes, depression, changes in libido insomnia, headache, migraine, acne, breast tenderness, breast pain, fluid retention and oedema, changes in menstrual flow, changes in body weight.

When should Norimin not be used?

You should not use Norimin tablets if you:

• are allergic to ethinyloestradiol or norethisterone, or any ingredients in Norimin
• are pregnant
• have liver disease
• a history of jaundice or cholestatic jaundice of pregnancy, or severe generalised itch in the body during pregnancy, Dubin Johnson Syndrome or Rotor Syndrome
• have carcinoma of the breast, genital organs or endometrial carcinoma, or an oestrogen dependent neoplasia
• have abnormal vaginal bleeding of unknown cause
• have a past or family history of carcinoma of the breast or endometrial carcinoma
• have liver adenomas or carcinomas or a history of these tumours
• have sickle cell anaemia
• have otosclerosis (an ear disorder) which worsened in past pregnancies
• have a history of herpes during pregnancy
• have high blood pressure, lipid disorders or migraine
• have had deep venous thrombosis, thromboembolic disorders, heart attack or stroke
• have diabetes with changes to the blood vessels
• are taking medicines that interact with Norimin including as anticonvulsants like phenytoin and carbamazepin, barbiturates, anti-infectives like rifampicin, rifabutin, nevirapine, the antifungal griseofulvin, antibiotics like penicillin, tetracyclines, sulfamethoxazole and trimethoprim, preparations containing St John's Wort

What medications interact with Norimin?

Some medications interact with Norimin contraceptive tablets and prevent them working effectively, increasing your risk of becoming pregnant.  If you are taking any of the following you may need to take other contraceptive precautions: phenytoin and carbamazepin, barbiturates, anti-infectives like rifampicin, rifabutin, nevirapine, the antifungal griseofulvin, antibiotics like penicillin, tetracyclines, sulfamethoxazole and trimethoprim, preparations containing St John's Wort.

What are the health risks of Norimin?

Combination contraceptive tablets like Norimin can increase risk of thrombosis (blood clots), which can have serious consequence depending on where the clot forms.  There is also an increased risk of breast cancer. 

How should Norimin be taken?

Each pack of Norimin contraceptive tablets contains 28 tablets for a complete monthly cycle and should be taken continually to ensure effective contraception.  When taking Norimin for the first time, take the first blue pill (corresponding to the day of the week) on the first day of your menstrual bleed and then take Norimin continually.  The first 21 blue tablets contain the contraceptive hormones and the last 7 orange tablets are a placebo, which do not contain any hormones.  While you are taking these placebo tablets you will have a menstrual bleed.  When you have finished one pack, start a new one the next day.  If you have gastrointestinal problems like vomiting or diarrhoea within 3-4 hours of taking your hormonal pill, this is the same as missing a pill and you should take other contraceptive precautions for the next 7 days.  You should take Norimin contraceptive tablets for as long as recommended by your doctor.

How long should you take Norimin?

Each pack of Norimin contraceptive tablets contains 28 tablets for a complete monthly cycle and should be taken continually to ensure effective contraception.  You should take Norimin contraceptive tablets for as long as recommended by your doctor.

Missed dose of Norimin

If you miss a dose of Norimin follow these guidelines to help you decide what to do:

Weeks 1 to 3 (blue hormonal tablets)

• If you are less than 12 hours late in taking your pill, take it as soon as you remember and take the next one at your usual time.  You are still protected against pregnancy.
• If you are more than 12 hours late in taking your pill, take the next one at your normal time and ignore the missed pill. Contraceptive protection may be reduced and you are at risk of becoming pregnant, unless you take other contraceptive precautions for the next 7 days.  If the 7 days extends into week for (orange tablets) start a new pack on the day after your last blue hormonal pill and discard the current pack, you will not have a menstrual bleed until you finish the second pack.

Week 4 (orange non-hormonal tablets)

Take the next pill as usual and discard the missed pill.  You are not at risk of becoming pregnant.

How should Norimin be stored?

You should store your Norimin below 25°C in a cool dry place.