Ibrance 100mg Tablets

Palbociclib is an orally available, selective inhibitor of cyclin-dependent kinases (CDK) 4 and 6. These kinases are activated by binding to D-cyclins and play a crucial role in cell cycle progression from G1 to S phase. By inhibiting CDK4/6, palbociclib prevents phosphorylation of the retinoblastoma protein (Rb), thereby blocking cell cycle progression and inhibiting tumor cell proliferation in HR-positive, HER2-negative breast cancer.

Urgent Side Effects: Seek Medical Help Right Away

Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:

Signs of an allergic reaction: rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat
Signs of infection: fever, chills, severe sore throat, ear or sinus pain, cough, increased or changed sputum production, painful urination, mouth sores, or a wound that won't heal
Signs of bleeding: vomiting or coughing up blood, coffee ground-like vomit, blood in the urine, black, red, or tarry stools, gum bleeding, abnormal vaginal bleeding, unexplained or enlarging bruises, or uncontrollable bleeding
Dizziness
Lung problems: new or worsening symptoms such as chest pain, cough (with or without mucus), or shortness of breath or other breathing difficulties (note: lung problems can be fatal)
Signs of a blood clot: chest pain or pressure, coughing up blood, shortness of breath, swelling, warmth, numbness, color change, or pain in a leg or arm, or trouble speaking or swallowing

Other Possible Side Effects

Like all medications, this drug can cause side effects. Many people experience no side effects or only mild ones. If you're bothered by any of the following side effects or if they persist, contact your doctor or seek medical help:

Hair loss or thinning
Mouth irritation or sores
Fatigue or weakness
Dry skin
Changes in taste
Diarrhea, vomiting, stomach upset, or decreased appetite (common side effects; consult your doctor for ways to minimize them)

If any of these side effects are severe, don't improve, or bother you, contact your doctor for guidance.

Reporting Side Effects

This list is not exhaustive. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.

Before Taking This Medication: Important Information to Share with Your Doctor

It is essential to inform your doctor about the following:

Any allergies you have, including allergies to this medication, its components, or other substances. Be sure to describe the allergic reaction and its symptoms.
Any medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins, that may interact with this medication. Certain medications used to treat HIV, infections, seizures, and other conditions should not be taken with this drug.
If you are breastfeeding or plan to breastfeed. You should not breastfeed while taking this medication and for 3 weeks after your last dose.

Please note that this is not an exhaustive list of all potential drug interactions or health problems that may affect your use of this medication. To ensure your safety, it is crucial to:

Inform your doctor and pharmacist about all your medications (prescription and OTC), natural products, vitamins, and health problems.
Verify that it is safe to take this medication with your existing medications and health conditions.
Never start, stop, or change the dose of any medication without first consulting your doctor.

It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.

While taking this drug, you may be at a higher risk of developing infections, some of which can be severe or even life-threatening. To minimize this risk, practice good hygiene by washing your hands frequently and avoid close contact with individuals who have infections, colds, or flu.

Additionally, this medication may increase your tendency to bleed easily. To reduce the risk of injury, exercise caution in your daily activities and use a soft toothbrush and an electric razor for personal grooming.

Regular blood tests and other laboratory evaluations are crucial while taking this medication. Ensure that you adhere to the schedule recommended by your doctor for these tests.

This drug is often administered in conjunction with other medications. It is vital to understand the warnings, benefits, and risks associated with these other drugs. If you have any questions or concerns, discuss them with your doctor.

To avoid potential interactions, refrain from consuming grapefruit and grapefruit juice while taking this medication.

Men taking this drug should be aware that it may affect their fertility. Discuss any concerns with your doctor.

For women, it is crucial to note that this medication can cause harm to an unborn baby. A pregnancy test will be conducted before initiating treatment to confirm that you are not pregnant. If you are of childbearing potential, use effective birth control methods during treatment and for at least 3 weeks after your last dose. If you become pregnant, notify your doctor immediately.

If your partner may become pregnant, it is recommended that they use birth control during your treatment and for 3 months after your last dose. If your partner becomes pregnant, contact the doctor right away.

• Strong CYP3A inhibitors (e.g., ketoconazole, itraconazole, clarithromycin, ritonavir, grapefruit juice): May significantly increase palbociclib exposure, leading to increased toxicity. Avoid concomitant use or reduce palbociclib dose.
• Strong CYP3A inducers (e.g., rifampin, carbamazepine, phenytoin, St. John's Wort): May significantly decrease palbociclib exposure, leading to reduced efficacy. Avoid concomitant use.

• Moderate CYP3A inhibitors (e.g., erythromycin, diltiazem, verapamil, fluconazole): May increase palbociclib exposure. Monitor for toxicity and consider dose reduction.
• Moderate CYP3A inducers (e.g., bosentan, efavirenz, modafinil): May decrease palbociclib exposure. Monitor for reduced efficacy.

• CYP3A substrates (e.g., midazolam, tacrolimus, sirolimus): Palbociclib is a weak time-dependent inhibitor of CYP3A. Monitor for increased exposure of sensitive CYP3A substrates.

• Fever (especially with neutropenia)
• Signs of infection (sore throat, chills, fatigue)
• Unusual bleeding or bruising
• Severe fatigue
• Diarrhea
• Nausea/vomiting
• Stomatitis/mouth sores
• Hair thinning/loss
• Rash
• Shortness of breath, cough, chest pain (signs of interstitial lung disease/pneumonitis)

Palbociclib can cause fetal harm when administered to a pregnant woman. Based on animal studies and its mechanism of action, it is expected to cause adverse developmental effects. Advise pregnant women of the potential risk to a fetus.

It is not known whether palbociclib is excreted in human milk. Because of the potential for serious adverse reactions in breastfed infants, advise lactating women not to breastfeed during treatment with palbociclib and for 3 weeks after the last dose.

The safety and effectiveness of palbociclib in pediatric patients have not been established. It is not indicated for use in pediatric patients.

No overall differences in safety or effectiveness were observed between patients ≥65 years of age and younger patients. No dose adjustment is required based on age alone.

• Always administer palbociclib with food to ensure consistent absorption and reduce variability.
• Strict adherence to the 21-day on, 7-day off schedule is crucial for managing myelosuppression, particularly neutropenia.
• Neutropenia is the most common adverse reaction and is often reversible and manageable with dose interruptions and/or reductions. Monitor CBCs diligently.
• Educate patients on signs of infection and to report fever immediately.
• Counsel patients on avoiding strong CYP3A inhibitors (e.g., grapefruit) and inducers (e.g., St. John's Wort).
• Consider dose adjustments for moderate to severe hepatic impairment and severe renal impairment.
• Be vigilant for new or worsening respiratory symptoms, as interstitial lung disease/pneumonitis can occur and may be severe or fatal.

• Other endocrine therapies (e.g., tamoxifen, anastrozole, letrozole, exemestane, fulvestrant)
• Chemotherapy regimens (e.g., capecitabine, eribulin, paclitaxel)
• Everolimus (Afinitor) + Exemestane

If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe and effective treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it is a good idea to consult with your pharmacist. If you have any questions or concerns about this medication, do not hesitate to discuss them with your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide detailed information about the overdose, including the medication taken, the amount, and the time it occurred.