Ibrance (palbociclib) is a capsule or tablet you take by mouth to treat certain types of breast cancer, specifically hormone receptor-positive, human epidermal growth factor 2-negative (HR+, HER2‑) advanced or metastatic breast cancer. It works by blocking specific proteins called CDK4/6 to help slow down the growth of cancer cells. You usually take it once a day for 21 days, and then don’t take it for 7 days, repeating this cycle every 28 days. Ibrance (palbociclib) is also used with other medications like an aromatase inhibitor, fulvestrant, or inavolisib. Side effects include low white blood cell counts, infections, nausea, and tiredness.
Advanced or metastatic breast cancer (HR+, HER2-), used with
An aromatase inhibitor as the first hormone-based treatment OR
Fulvestrant after the cancer has stopped responding to hormone-based treatment
Advanced or metastatic breast cancer (HR+, HER2-) with a PIK3CA mutation, used with inavolisib and fulvestrant after the cancer has come back following hormone therapy
Ibrance (palbociclib) is a cyclin-dependent kinase 4 and 6 (CDK 4/6) inhibitor. CDK 4/6 are proteins that help control how cells grow. In cancer, these proteins can become too active, causing cells to grow and divide too quickly. Ibrance (palbociclib)] blocks these proteins to help slow down the growth of cancer cells.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
Oral pill taken at home
Recommended treatment option for advanced or metastatic breast cancer (HR+, HER2-)
Helps you live longer without the cancer getting worse compared to hormone therapy alone
Raises your risk for infections, some of which can be serious
Requires regular blood tests to check white blood cell count
Not safe to take while pregnant or breastfeeding
If you're taking the capsule form of Ibrance (palbociclib), take it with food at the same time every day. This helps your body absorb the medication better. Swallow the capsules whole — don’t chew, crush, or open them.
If you’re taking the tablet form, you can take it with or without food at the same time each day. Swallow the tablets whole — don’t chew, crush, or split them.
If you miss a dose of Ibrance (palbociclib) or vomit after taking it, don’t take an extra dose that day. Just take your next dose at your regular time.
You should take Ibrance (palbociclib) at the same time as another cancer medication like an aromatase inhibitor, fulvestrant, or inavolisib. These medications work together to treat your cancer. Ask your oncologist if you’re not sure whether you're taking one.
Avoid grapefruit and grapefruit juice while taking Ibrance (palbociclib). They can raise the amount of the medication in your body and lead to more side effects.
Tell your oncologist and pharmacist about all medications and supplements you take while using Ibrance (palbociclib). Some medications can interact and cause more side effects or make the treatment not work as well.
Let your oncologist know right away if you have signs of low blood counts or infection while taking Ibrance (palbociclib). This includes fever, chills, dizziness, trouble breathing, weakness, or easy bruising or bleeding. These could be signs of a serious problem.
Tell your oncologist if you have new or worse breathing problems while taking Ibrance (palbociclib). Trouble breathing or shortness of breath might need medical attention.
Ibrance (palbociclib) isn’t safe to take during pregnancy since it can harm an unborn baby. Use birth control while taking it and for 3 weeks after your last dose. Let your oncologist know right away if you become pregnant.
Men with partners who can get pregnant should use birth control while taking Ibrance (palbociclib) and for at least 3 months after the last dose. If your partner becomes pregnant during this time, let your oncologist know right away
Don’t breastfeed while taking Ibrance (palbociclib). It’s not known if it passes into breast milk, but it could be harmful to a baby. Avoid breastfeeding during treatment and for 3 weeks after your last dose.
Ibrance (palbociclib) might lower your ability to have children, especially for men. Talk to your oncologist if you have concerns about fertility.
Ibrance (palbociclib) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Ibrance (palbociclib) often causes your white blood cell count to drop. When this happens, you might have a higher risk of getting an infection. Your oncologist will check your blood counts regularly during treatment. Let your care team know if you get a fever or start to feel sick. If your white blood cell count gets too low, your oncologist might pause your treatment, lower the dose, or delay your next cycle.
Rarely, Ibrance (palbociclib) can cause serious lung problems, like lung inflammation or interstitial lung disease. Tell your care team right away if you have new or worsening breathing problems like coughing or shortness of breath. They might have you stop taking the medication while they figure out what’s causing the problem.
Based on animal studies, Ibrance (palbociclib) might harm an unborn baby. If you can get pregnant, use birth control while taking it and for at least 3 weeks after your last dose. Men with partners who can get pregnant should use birth control during treatment and for at least 3 months after the last dose. Let your oncologist know right away if you or your partner becomes pregnant.
The typical dose is 125 mg by mouth for 21 days in a row, followed by 7 days off. Then, the cycle repeats every 28 days.
The dose might be different if you have liver problems or take other medications that interact with Ibrance (palbociclib).
Advanced or metastatic breast cancer (HR+, HER2-), used with
An aromatase inhibitor as the first hormone-based treatment OR
Fulvestrant after the cancer has stopped responding to hormone-based treatment
Advanced or metastatic breast cancer (HR+, HER2-) with a PIK3CA mutation, used with inavolisib and fulvestrant after the cancer has come back following hormone therapy
Early breast cancer (HR+, HER2-), used with an aromatase inhibitor in adults at high risk of the cancer coming back
Advanced or metastatic breast cancer (HR+, HER2-), used with
Early breast cancer (HR+, HER2-), used with tamoxifen or an aromatase inhibitor in adults at high risk of the cancer coming back
Advanced or metastatic breast cancer (HR+, HER2-), used with
Advanced or metastatic breast cancer (HR+, HER2-), used alone if the cancer has worsened after both hormone-based treatment and chemotherapy
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