Anti-estrogen (Hormonal anticancer agent)
Last reviewed June 2026
Who is this for?
Tamoxifen is a cancer medication that works by blocking the hormone estrogen from reaching breast cancer cells, which slows or stops the growth of tumors that depend on estrogen to grow.
Binds to estrogen receptors in breast tissue, competitively blocking estrogen-dependent gene transcription and inhibiting proliferation of estrogen-responsive breast cancer cells. Also exhibits partial agonist activity on estrogen receptors in other tissues, contributing to its therapeutic effects in hormone-sensitive breast malignancies.
Prescription Required
You need a doctor's prescription to buy this drug.
Explore this drug
The usual dose is one 20 mg tablet taken once daily or split into two 10 mg doses taken morning and evening. Swallow the tablet whole with water. You can take it with or without food, but try to take it at the same time every day. Your doctor will tell you how long to take it — this is usually for 5 to 10 years, so do not stop on your own.
If you miss a dose, take it as soon as you remember. But if it is almost time for your next dose, skip the missed one and continue your regular schedule. Do not take two tablets at once to make up for the missed dose.
Only buy tamoxifen from registered pharmacies — do not buy from roadside vendors or unverified online sellers, as fake cancer drugs are very dangerous. This is a long-term medication, so do not stop taking it because you feel fine — your doctor will tell you when to stop. Do not share this medication with anyone else, even if they also have breast problems — they must see a doctor first.
Avoid taking tamoxifen with blood thinners like warfarin, as it can increase the risk of bleeding. Some antidepressants (like fluoxetine and paroxetine) can reduce how well tamoxifen works — tell your doctor about all medications you are taking. Limit alcohol intake as it may increase the risk of side effects and can also raise breast cancer risk.
Check your specific combination
Is it safe to take Tamoxifen with your other drugs?
Tamoxifen is NOT safe during pregnancy or breastfeeding — it can cause serious harm to an unborn baby, so use reliable contraception while taking it and tell your doctor immediately if you become pregnant.
Store in a cool, dry place away from direct sunlight and heat — Nigerian weather can be very hot, so avoid leaving it in cars or near windows. Keep it in its original container and far away from children.
For information only — not medical advice. Always talk to a doctor or pharmacist before changing your medication.
Names this drug is sold under — especially in Nigerian and West African pharmacies
Tap a brand for packaging, NAFDAC details and authenticity check
Counterfeit Drug Warning
Fake drugs are a serious problem in Nigeria. Always buy from a registered pharmacy. If the packaging looks different from what is described above, do not use it.
Dispensing Tamoxifen?
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