What is ribociclib?
Ribociclib is used to treat hormone-related breast cancer in women. Ribociclib is used only if your cancer tests negative for a protein called human epidermal growth factor receptor 2 (HER2). HER2 protein can speed the growth of cancer cells.
Ribociclib is used when the cancer has progressed or has spread to other parts of the body after other treatments.
Ribociclib is given in combination with another cancer medicine such as letrozole (Femara) or fulvestrant (Faslodex).
Ribociclib can cause serious side effects on your heart, liver, or lungs. Call your doctor at once if you have chest pain, fast or pounding heartbeats, trouble breathing, cough (with or without mucus), sudden dizziness, right-sided upper stomach pain, loss of appetite, unusual bleeding or bruising, dark urine, or yellowing of your skin or eyes.
You will need frequent medical tests while taking ribociclib. Your cancer treatments may be delayed based on the results of these tests. Tell your doctor if you have signs of infection, such as fever or chills.
Before taking this medicine
You should not use ribociclib if you are allergic to it, or if you also take tamoxifen.
Your doctor will perform blood tests to make sure you do not have conditions that would prevent you from safely using ribociclib.
Tell your doctor if you have ever had:
- slow heartbeats;
- heart disease or prior heart attack;
- long QT syndrome;
- an electrolyte imbalance (such as low levels of calcium, magnesium, phosphorus, or potassium in your blood);
- liver disease;
- kidney disease; or
- signs of infection (fever, chills).
Tell your doctor whether or not you have gone through menopause.
You may need to have a negative pregnancy test before starting this treatment.
Do not use ribociclib if you are pregnant. It could harm the unborn baby. Use effective birth control to prevent pregnancy while you are using ribociclib and for at least 3 weeks after your last dose.
This medicine may affect fertility (ability to have children) in men. Talk with your doctor if you have concerns about this risk.
You should not breastfeed while using this medicine and for at least 3 weeks after your last dose.
How should I take ribociclib?
Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.
Ribociclib is given in a 28-day treatment cycle. You will take the medicine for the first 21 days of each cycle, followed by 7 days off. Your doctor will determine how long to treat you with ribociclib.
Swallow the tablet whole and do not crush, chew, or break it.
Take the medicine at the same time each morning, with or without food.
If you vomit after taking the medicine, wait until the next day to take your next dose.
Do not use a broken or damaged pill.
You may need frequent medical tests to be sure ribociclib is not causing harmful effects. Your cancer treatments may be delayed based on the results.
Store ribociclib in the original container at room temperature, away from moisture and heat.
What happens if I miss a dose?
Skip the missed dose. Take your next dose at the regular time and stay on your once-daily schedule. Do not use 2 doses in one day.
What should I avoid while taking ribociclib?
Grapefruit may interact with ribociclib and lead to unwanted side effects. Avoid the use of grapefruit products.
Avoid taking an herbal supplement containing St. John’s wort at the same time you are taking ribociclib.
Ribociclib side effects
Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
Seek medical treatment if you have a serious drug reaction that can affect many parts of your body. Symptoms may include: skin rash, fever, swollen glands, muscle aches, severe weakness, unusual bruising, or yellowing of your skin or eyes.
Call your doctor at once if you have:
- fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness (like you might pass out);
- low white blood cell counts–fever, mouth sores, skin sores, sore throat, cough, trouble breathing;
- signs of inflammation in the lungs–new or worsening cough, painful or difficult breathing, wheezing, feeling short of breath even while resting; or
- liver problems–loss of appetite, upper stomach pain, tiredness, easy bruising or bleeding, dark urine, jaundice (yellowing of the skin or eyes).
Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.
Common side effects may include:
- low white blood cells, infections;
- nausea, vomiting;
- diarrhea, constipation;
- feeling tired;
- headache; or
- hair loss.