Palbociclib (palbociclib) — Uses, Dosage, Side Effects & Safety

Drug class: Cyclin-dependent kinase (CDK) 4/6 inhibitor

Overview

Palbociclib is a targeted cancer medicine used to treat certain types of advanced or metastatic breast cancer. It is typically prescribed in combination with hormone therapies such as letrozole or fulvestrant for hormone receptor-positive, HER2-negative breast cancer in adults. Palbociclib works by blocking proteins called cyclin-dependent kinases 4 and 6 (CDK4/6), which are involved in cell division. By inhibiting these proteins, palbociclib helps slow down or stop the growth of cancer cells. Key points for patients: Palbociclib is taken by mouth, usually once daily for 21 days followed by a 7-day break. It is important to take the medication exactly as prescribed and to report any side effects, especially signs of infection or unusual bruising.

Therapeutic uses

• Hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer in combination with an aromatase inhibitor as initial endocrine-based therapy in postmenopausal women or in men
• Hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer in combination with fulvestrant in women with disease progression following endocrine therapy
• Hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer in combination with fulvestrant in men with disease progression following endocrine therapy

Common side effects

• Neutropenia
• Leukopenia
• Anemia
• Thrombocytopenia
• Fatigue
• Nausea
• Diarrhea
• Infections

Frequently Asked Questions about Palbociclib

What is palbociclib used for?

Palbociclib is used to treat hormone receptor-positive, HER2-negative advanced or metastatic breast cancer, usually in combination with hormone therapy.

How should I take palbociclib?

Take palbociclib once daily with food, at the same time each day, for 21 days followed by a 7-day break. Swallow the capsule or tablet whole.

What are the most common side effects?

The most common side effects are low white blood cell counts, fatigue, nausea, mouth sores, diarrhea, and hair thinning.

Can I take palbociclib if I am pregnant or breastfeeding?

No. Palbociclib may harm an unborn baby and is not recommended during pregnancy or breastfeeding. Use effective contraception during treatment.

What should I do if I miss a dose?

Skip the missed dose and take your next dose at the usual time. Do not double up doses.

Are there foods or medicines I should avoid?

Avoid grapefruit products and strong CYP3A inhibitors or inducers. Discuss all medications and supplements with your doctor.

How will my doctor monitor my treatment?

Your doctor will regularly check your blood counts and monitor for side effects to ensure safe and effective treatment.

Educational information only. Always consult a qualified healthcare professional before starting, stopping, or changing any medication.