How do you take Alpelisib?

The usual adult dose is 300 mg taken once daily by mouth. Take it immediately after eating food, as this is very important to reduce side effects like nausea and high blood sugar. Swallow the tablets whole, do not crush or chew them. Your oncologist (cancer doctor) will tell you exactly how to combine it with fulvestrant injections.

What are the side effects of Alpelisib?

High blood sugar (you may feel very thirsty, urinate often, or feel tired), diarrhoea, skin rash or dry skin, nausea or loss of appetite, feeling very tired or weak

Who should not take Alpelisib?

People allergic to alpelisib or any ingredient in Pivikto tablets, people with a history of severe allergic skin reactions like Stevens-Johnson syndrome, people with poorly controlled diabetes or very high blood sugar, and anyone whose cancer does not have the specific PIK3CA gene change (your doctor must confirm this with a test before starting treatment).

Prescription

Targeted cancer therapy (PI3K inhibitor)

Alpelisib

Last reviewed July 2026

Who is this for?

For adults (18+). Standard adult dosing applies: see the How to Take tab for full instructions.

What is this drug?

Alpelisib (sold as Pivikto in Nigeria) is a cancer medicine that works by blocking a specific protein called PI3K-alpha, which helps cancer cells grow and multiply. By blocking this protein, the drug slows down or stops the growth of certain breast cancers.

How it works

Inhibits phosphatidylinositol 3-kinase (PI3K), blocking the PI3K/AKT/mTOR signaling pathway that promotes cancer cell survival and proliferation in hormone receptor-positive breast cancers with PIK3CA mutations. Used with fulvestrant to enhance endocrine therapy by preventing compensatory pathway activation that drives treatment resistance.

What is it used for?

Advanced breast cancer (specifically hormone receptor-positive, HER2-negative breast cancer that has a PIK3CA gene change), used together with another cancer drug called fulvestrant

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Cancer Treatment

Prescription Required

You need a doctor's prescription to buy this drug.

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What to watch out for

This is a specialist cancer drug, so only take it if prescribed and monitored by an oncologist (cancer specialist). Never buy it from unverified sources or roadside sellers. Your doctor will need to check your blood sugar regularly throughout treatment, so attend all your clinic appointments. Do not share this medicine with anyone else, even if they have breast cancer, as it only works for a very specific cancer type confirmed by a lab test.

Common Side Effects

High blood sugar (you may feel very thirsty, urinate often, or feel tired)
diarrhoea
skin rash or dry skin
nausea or loss of appetite
feeling very tired or weak

Serious Side Effects

Severe allergic skin reactions like blistering
peeling skin
or mouth sores require you to stop the drug and go to the hospital immediately. Very high blood sugar that can become life-threatening requires you to watch for confusion
fast breathing
or fruity-smelling breath. Severe diarrhoea with dehydration also needs urgent medical attention.

Drug Interactions

Avoid taking Alpelisib with medicines that lower blood sugar (like metformin or insulin) without your doctor adjusting the doses, as it raises blood sugar significantly. Drugs like rifampicin (used for TB treatment) can reduce how well Alpelisib works. Avoid grapefruit and St. John's Wort as they can interfere with how your body processes this medicine.

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Pregnancy & Breastfeeding Warning

Alpelisib is NOT safe during pregnancy or breastfeeding, as it can seriously harm an unborn baby. Women must use effective contraception during treatment and for at least one week after the last dose.

Who Should NOT Take This

People allergic to alpelisib or any ingredient in Pivikto tablets
people with a history of severe allergic skin reactions like Stevens-Johnson syndrome
people with poorly controlled diabetes or very high blood sugar
and anyone whose cancer does not have the specific PIK3CA gene change (your doctor must confirm this with a test before starting treatment).

How to Store

Store below 30°C in a cool, dry place away from direct sunlight and humidity, which is important in Nigeria's hot climate. Keep in the original packaging and far out of reach of children. Do not use after the expiry date on the pack.

For information only: not medical advice. Always talk to a doctor or pharmacist before changing your medication.