Norethisterone (US, Norethindrone)
(Nor-reth-ist-er-rone) (nor eth in' drone)
P / L : Contraindicated in pregnancy and caution during lactation
|| See TERMINOLOGY & ABBREVIATIONS ||
|Indication(s) & Dosage||
|Administration||May be taken with or without food. May be taken w/ meals to minimise GI upset.
|Overdose||Symptoms include nausea, vomiting, breast enlargement, vaginal bleeding. Treatment should be symptomatic.|
|Contraindications||Severe hepatic dysfunction; undiagnosed vaginal bleeding; porphyria; pregnancy; previous idiopathic or current thromboembolism; thromboembolic disease; DVT.|
|Special Precautions||Hypertension; CVS disease; hepatic impairment; epilepsy; lactation; new onset of migraine-type headache; asthma; renal impairment; history of clinical depression.|
|Adverse Drug Reaction(s)||Mental depression, cholestatic jaundice, porphyria, epilepsy, migraine, headache, breast discomfort, dizziness, nausea and vomiting, changes in libido, appetite and weight, breakthrough bleeding, changes in menstrual flow, amenorrhoea, oedema, rash, melasma or cholasma, acne, urticaria, abnormal LFTs, moodswings, insomnia, thrombotic and thromoembolic events, optic neuritis, altered lipid profile.|
|Drug Interactions||Concentration may be reduced by CYP450 inducers (e.g. phenobarbital, phenytoin, carbamazepine, rifampicin, rifabutin, nevirapine, efavirenz, tetracyclines, ampicillin, oxacillin, co-trimoxazole) and ritonavir, nelfinavir (usually inhibitors of CYP450 but have inducing properties when used with steroid hormones). May cause additive fluid retention with NSAIDs, vasodilators. Adjustment in antidiabetic, thyroid hormone and anticoagulant therapy may be required.
Potentially Fatal: May increase ciclosporin concentration. Please consult detailed drug interactions before prescribing.
|Food Interaction||St John's wort may induce norethisterone metabolism, leading to decreased concentrations.|
|Lab Interference||Abnormal thyroid function tests, metyropone test and LFTs reported.|
|Pregnancy Category (FDA)||Category X: Studies in animals or human beings have demonstrated foetal abnormalities or there is evidence of foetal risk based on human experience or both, and the risk of the use of the drug in pregnant women clearly outweighs any possible benefit. The drug is contraindicated in women who are or may become pregnant.|
|Storage||Oral: Store below 25°C. Transdermal: Store below 25°C.|
|Pharmacology||Norethisterone has typical effects of a progestogen and converts the endometrium from the proliferative to the secretory phase. It may also have some oestrogenic, anabolic and androgenic activities, but these may not be significant. Norethisterone delays onset of periods and controls abnormal uterine bleeding. It also has contraceptive effects due to negative feedback inhibition of pituitary gonadotropin thus preventing ovulation.
Absorption: Absorbed from the GI tract (oral).
Distribution: Highly protein bound
Metabolism: Hepatic; extensive first-pass effect.
Excretion: Via urine (50-80%); via faeces (40%).
|ATC Classification||G03DC02 - norethisterone; Belongs to the class of estren derivative progestogens used in progestogenic hormone preparations.
G03AC01 - norethisterone; Belongs to the class of progestogens. Used as systemic contraceptives.
|Brand Name||Manufacturer/Marketer||Composition||Dosage Form||Pack Size & Price|
|ETHINOR||Eskayef Bangladesh Ltd||Norethisterone Acetate BP 5.75mg equivalent to 5mg Norethisterone||Tablet||45's MRP: 225.00|
|MENORAL||Square Pharmaceuticals Ltd.||Norethisterone 5mg||Tablet||3x10's: 150.60 MRP|
|NORCOLUT||Gedeon Richter/City Overseas||Norethisterone 5mg||Tablet||20's: 145.00 TP|
|NORMENS||Renata Limited||Norethisterone 5mg||Tablet||60's: 301.20 MRP|
|Noteron||Incepta Pharmaceuticals Limited||5.75mg Norethisterone Acetate BP equivalent to 5mg Norethisterone||Tablet||15x4's:MRP 300 Tk|
|REMENS||Popular Pharmaceuticals Ltd.||Norethisterone 5mg||Tablet||60's: 300.00 MRP|
Why is this medication prescribed?
Norethisterone/Norethindrone is used to treat endometriosis, a condition in which the type of tissue that lines the uterus (womb) grows in other areas of the body and causes pain, heavy or irregular menstruation (periods), and other symptoms. Norethisterone/Norethindrone is also used to treat abnormal periods or bleeding and to bring on a normal menstrual cycle in women who menstruated normally in the past but have not menstruated for at least 6 months and who are not pregnant or undergoing menopause (change of life). Norethisterone/Norethindrone is also used as a test to see if the body is producing certain female hormones (natural substances that affect the uterus). Norethisterone/Norethindrone is in a class of medications called progestins. It works by stopping the lining of the uterus from growing and by causing the uterus to produce certain hormones.
Norethisterone/Norethindrone is also used to prevent pregnancy. Norethisterone/Norethindrone is sold under different brand names and is taken in smaller amounts when it used to prevent pregnancy. This section does not include information on the use of Norethisterone/Norethindrone to prevent pregnancy. If you would like more information on that use of Norethisterone/Norethindrone, read the monograph called 'PROGESTIN / PROGESTOGEN ONLY CONTRACEPTIVE (ORAL)'.
How should this medicine be used?
Norethisterone/Norethindrone comes as a tablet to take by mouth. Norethisterone/Norethindrone is taken on different schedules that depend on the condition that is being treated and on how well Norethisterone/Norethindrone works to treat the conditions. When Norethisterone/Norethindrone is used to treat endometriosis, it is usually taken once a day for 6 to 9 months or until breakthrough bleeding becomes bothersome. When Norethisterone/Norethindrone is used to bring on a normal cycle in women who have stopped menstruating, it is usually taken once a day for 5 to 10 days during the second half of the planned menstrual cycle. To help you remember to take Norethisterone/Norethindrone, take it at around the same time of day every day that you are scheduled to take it. Follow the directions on your prescription label carefully, and ask your doctor to explain any part you do not understand. Take Norethisterone/Norethindrone exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
If you are taking Norethisterone/Norethindrone for endometriosis, your doctor will probably start you on a low dose of Norethisterone/Norethindrone and gradually increase your dose, not more than once every 2 weeks.
Norethisterone/Norethindrone may control your condition but will not cure it. Continue to take Norethisterone/Norethindrone even if you feel well. Do not stop taking Norethisterone/Norethindrone without talking to your doctor.
Other uses for this medicine
This medication may be prescribed for other uses; ask your doctor for more information.
What special precautions should I follow?
Before taking Norethisterone/Norethindrone,
- tell your doctor if you are allergic to Norethisterone/Norethindrone, oral contraceptives ('birth control pills'), or any other medications.
- tell your doctor what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention medications for seizures such as carbamazepine (Tegretol),phenobarbital (Luminal, Solfoton), and phenytoin (Dilantin); and rifampin (Rifadin, Rimactane). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have recently had surgery or have been unable to move around for any reason and if you have or have ever had breast cancer; unexplained vaginal bleeding; a missed abortion (a pregnancy that ended when the unborn child died in the uterus but was not expelled from the body); blood clots in your legs, lungs, brain, or eyes; stroke or mini-stroke; coronary artery disease (clogged blood vessels leading to the heart); chest pain; a heart attack; thrombophilia (a condition in which the blood clots more easily); seizures; migraine headaches; depression; asthma; high cholesterol; diabetes; or heart, kidney, or liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking Norethisterone/Norethindrone, call your doctor immediately. Norethisterone/Norethindrone should never be used to test for pregnancy.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking Norethisterone/Norethindrone.
- tell your doctor if you smoke cigarettes. Smoking may increase the risk that you will develop serious side effects of Norethisterone/Norethindrone.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do if I forget a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What side effects can this medication cause?
Norethisterone/Norethindrone may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
irregular vaginal bleeding or spotting
changes in menstrual flow
enlarged or tender breasts
difficulty falling asleep or staying asleep
growth of hair on face
Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them, call your doctor immediately:
loss of vision
pain, warmth, or heaviness in the back of the lower leg
shortness of breath
coughing up blood
sudden sharp or crushing chest pain
heaviness in chest
slow or difficult speech
dizziness or faintness
weakness or numbness of an arm or leg
swelling of the arms, hands, feet, ankles, or lower legs
yellowing of the skin or eyes
brown patches on the face
sudden, severe pain in the abdomen (area between the chest and waist)
difficulty breathing or swallowing
Norethisterone/Norethindrone may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
What should I know about storage and disposal of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of emergency/overdose
In case of overdose, consult your doctor. If the victim has collapsed or is not breathing, consult local medical emergency services.
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to this medicine.
Do not let anyone else use your medication. If you still have symptoms and need further treatment, consult your doctor.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
Ref: MedlinePlus, U.S. National Library of Medicine.
This information is provided for reference only and not a replacement for and should only be used in conjunction with full consultation with a registered medical practitioner. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, mph-bd shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise.
|| See FDA approved Prescribing Information from Manufacturer |||Manufacturer's|
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