Norinyl 1+50 is a monophasic high dose birth control prescribed to prevent pregnancy. It contains mestranol and norethindrone with properties of ovulation suppression.
Indications for use
Norinyl 1+50 is prescribed as contraception (pregnancy prevention).
Mechanism of action
Norinyl 1+50 relates to a combined hormonal birth control having anti-aldosterone and anti-androgenic properties. The contraceptive effect of this hormonal birth control is grounded on the cooperation of various patterns. The most significant property is ovulation suppression. It also alters cervical secretions’ properties. It contributes to the fact of almost impossibility for sperm to enter uterine cavity.
Mode of application and dosage
You should start taking Norinyl 1+50 on the first day of the menstrual cycle. Take 1 pill daily for 21 days. Then, you have to take 7 pills containing no hormone. After labor, this birth control drug is started taking after 4 weeks. The drug should be withdrawn 4-6 weeks prior to surgery and begin no earlier than 2 weeks after it. Vomiting or diarrhea can lead to the excretion of the drug taken from the body, therefore, in cases when these symptoms disappear within 1 day, the pill must be taken repeatedly.
Norinyl 1+50 cannot be taken in the following medical conditions:
- thromboembolism (impaired vascular patency);
- liver tumors;
- breast cancer;
- estrogen-dependent tumors;
- vascular diseases of the brain or coronary (cardiac) arteries;
- uterine bleeding of unknown etiology (cause);
- uterine cancer;
- vaginal cancer;
- cholestatic jaundice (yellowing).
The risk of cardiovascular complications increases if a woman smokes especially after 35 years old. Before starting to take Norinyl 1+50 on a regular basis, gynecologist’s consultations are mandatory.
The drug is immediately withdrawn if the following symptoms appear:
- early signs of phlebitis (inflammation of the vein wall);
- thrombosis (vascular occlusion with a blood clot);
- emboli (vascular impairment);
- unusual pain in the legs;
- chest pain during breathing or coughing;
- a feeling of chest tightness;
- first-time migraine-like headaches;
- sudden impairment of hearing;
- visual impairments;
- movement disorders.
The risk of thrombosis increases if a woman suffers from high blood pressure. The drug is discontinued if having the following diagnosis:
- increased epilepsy attacks;
- primary or secondary porphyria appearance (diseases associated with impaired metabolism of porphyrins/pigments).
Norinyl 1+50 can become a cause of the following side effects:
- thrombophlebitis (inflammation of the walls of the veins with their blockage);
- arterial thromboembolism (impaired vascular permeability);
- myocardial infarction;
- cerebral hemorrhage;
- thrombosis (blockage of blood clots);
- dyspepsia (digestive disorders);
- impaired liver and/or kidney function;
- menstrual disorder.
If to speak about possible side effects of Norinyl 1 + 50 if specify body systems the following negative reactions may be observed:
- nervous system: headache, emotional lability, depression, decreased libido, increased libido.
- endocrine system: violations of the menstrual cycle, intermenstrual bleeding, pain in the mammary glands, secretions from the mammary glands.
- organs of senses: hearing loss, intolerance to contact lenses.
- digestive system: nausea, abdominal pain, vomiting, diarrhea.
- skin and subcutaneous tissue: acne, eczema, skin rash, urticaria, erythema nodosum, erythema multiforme, pruritus, chloasma.
- vascular system: migraine, hypotension or hypertension, thrombosis (venous and arterial), thromboembolism.
- systemic disorders: an increase in body weight, fluid retention, weight loss.
- immune system: bronchospasm.
- reproductive system and mammary glands: acyclic vaginal bleeding, tenderness, enlargement of the mammary glands, vaginal candidiasis, vaginitis, secretions from the mammary glands, an increase in vaginal secretions.
The clearance of sex hormones can be increased if Norinyl 1+50 is combined with the drugs that induce liver microsomal enzymes. Such clearance increase can result in breakthrough uterine bleeding and/or to a decrease in the contraceptive reliability.
Substances that magnify the clearance of mestranol and norethindrone (weaken the effectiveness by enzymes’ induction) are phenytoin, barbiturates, bosentan, primidone, carbamazepine, rifampicin and HIV treatment agents (ritonavir, nevirapine and efavirenz). This group may possibly include the following substances as oxcarbazepine, topiramate, felbamate, griseofulvin, as well as remedies in the composition of which has St. John’s wort.
When used in combination with this birth control drug, many HIV protease or hepatitis C virus inhibitors and non-nucleoside reverse transcriptase inhibitors can have the following results: an increase or reduction in the concentration of estrogen or progestin in the blood plasma. In some cases, this effect may be clinically significant.
What if I miss a dose?
A woman can neglect the missing of placebo pills as they have no influence on the contraceptive reliability.
If the missing in taking Norinyl 1+50 was less than 24 hours, have no reason to be anxious. A woman cannot become pregnant. A woman should take the missed pill as soon as possible and take the next pill at the regular time of the day.
If the missing in taking these contraceptive pills is more than 24 hours, the contraceptive reliability can be decreased. The more missed pills and the closer the pill missing to the placebo pills, the risk to conceive a child is greater. To exclude pregnancy, it is necessary to use additional barrier contraceptive methods.
Norinyl 1 + 50 and pregnancy
Norinyl is contraindicated during pregnancy. If a woman plans to have a baby, she can withdraw the medication at any time. If pregnancy is diagnosed during the drug usage, it should be discontinued immense. There were conducted epidemiological researches which have not discovered any increased risk relating to developmental defects in children whose mothers took sex hormones before becoming pregnant. They also have not confirmed a teratogenic effect, which may appear when a woman uses sex hormones at the early stages of pregnancy.
There is no scientific confirmation to the fact of possible defects in fetus or newborn if a woman takes combined birth control.
Use of Norinyl 1 + 50 during a lactating period is contraindicated. The application of combined hormonal contraceptives can decrease the volume of breast milk and change its composition. So that, their usage is prohibited till the moment breastfeeding is arrested. A small number of sex hormones and/or their components can become a part of breast milk affecting the newborn body.