Olaparib

Say it: oh-LAP-a-rib · Brand names: Lynparza

Olaparib is a targeted therapy pill called a PARP inhibitor that stops cancer cells from repairing their damaged DNA.

What it is

Cells use proteins called PARP to fix damaged DNA. Cancer cells with certain gene changes, such as BRCA, already have trouble fixing DNA. When olaparib blocks PARP, these cancer cells cannot repair themselves and die.

Often used for

• ovarian, fallopian tube, or primary peritoneal cancer
• breast cancer with an inherited BRCA gene change
• pancreatic cancer with an inherited BRCA gene change
• prostate cancer with certain gene changes

How you get it

Olaparib is a pill you take by mouth at home, twice a day, about 12 hours apart, with or without food. Your schedule may be different.

Common side effects and what helps

• Feeling sick to your stomach or throwing up. Eat small meals and ask your team about anti-nausea medicine.
• Feeling tired or weak. Rest when you need to, and try short walks.
• Low red blood cells (anemia), which can make you tired or short of breath. You will have blood tests to check.
• Diarrhea. Drink plenty of fluids. Tell your team early, since they may give you medicine to help.
• Not feeling hungry or losing weight. Try small, frequent meals and snacks.
• Headache or dizziness. Stand up slowly.
• Changes in how food tastes. Try new flavors and keep your mouth clean.
• Cough or shortness of breath. Tell your team if it is new or gets worse.

Call your care team right away if you have

• A fever of 100.4 degrees Fahrenheit (38 degrees Celsius) or higher, or chills
• Unusual bruising or bleeding, feeling very weak or tired, or getting infections often
• New or worse cough, chest pain, or trouble breathing
• Swelling, pain, or warmth in one leg, or sudden shortness of breath
• Blood in your urine or stool

Before you start, tell your team

• If you are pregnant, may become pregnant, or are breastfeeding
• If you have kidney problems
• If you have had blood clots
• All the medicines, vitamins, and herbal products you take, since some can change how this medicine works

Good to know

• You will have blood tests to check your blood counts before starting and every month.
• Rarely, it can cause a serious blood or bone marrow cancer. Tell your team if you feel very tired, lose weight, bruise easily, or get fevers or infections often.
• It can raise the chance of blood clots and, rarely, lung inflammation.
• This medicine can harm an unborn baby. Use birth control during treatment and for some time after. Ask your team how long.

At home

• Take the tablets at about the same times each day.
• Swallow the tablets whole. Do not chew, crush, or split them.
• Do not eat grapefruit or drink grapefruit juice while taking this medicine.
• If you miss a dose or throw up after taking it, ask your team what to do. Do not take extra pills to make up for it.
• Store the pills at room temperature in the original bottle, away from children and pets.

Questions to ask

• How long will I take this medicine?
• Do I have a gene change that this medicine targets?
• Should my family members think about genetic testing?
• Which side effects should I call about right away, and which can wait until my next visit?

Side effect guides

• Fatigue (tiredness)
• Nausea and vomiting
• Diarrhea
• Taste changes
• Anemia (low red blood cells)
• Shortness of breath
• Cough

Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.