Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Abnormal heart rhythm: This medication can cause abnormal heart rhythms, especially for people who have certain heart problems (e.g., congenital long QT syndrome), who are taking medication(s) to control heart rhythm (e.g., amiodarone, disopyramide, quinidine, sotalol), who have received high doses of anthracycline chemotherapy (e.g., daunorubicin, doxorubicin, mitoxantrone), or who are prone to low potassium and magnesium blood levels. Your doctor can assess your risk by reviewing your medications and checking your blood and electrocardiogram (ECG).
Anemia: Dasatinib may cause low levels of red blood cells. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired or pale skin, contact your doctor as soon as possible.
Your doctor will do blood tests regularly to monitor the number of specific types of blood cells, including red blood cells, and adjust your dose or temporarily stop it. In severe cases, you may need to receive transfusions of red blood cells.
Bleeding: Dasatinib may cause bleeding from various sources. The most serious bleeding may occur in the stomach and the brain. If you experience signs of stomach bleeding (severe stomach pain, black stools, vomiting blood, dizziness) or bleeding into the brain (severe and sudden headache, dizziness, trouble speaking, numbness, or weakness), get immediate medical attention.
Blood counts: This medication can decrease the number of red blood cells (anemia), white blood cells (neutropenia), and platelets (thrombocytopenia). Your doctor will do blood tests to monitor for this and adjust your dose of dasatinib or temporarily stop it if your blood counts are too low. If you develop a fever while your blood cell counts are low, contact your doctor immediately.
Congestive heart failure: People taking dasatinib have experienced congestive heart failure (the heart is not able to pump blood efficiently). This is usually accompanied by fluid retention (see below) or fluid in the lungs (pulmonary edema). If you experience shortness of breath, swelling, or rapid weight gain, contact your doctor immediately.
Fertility: The effects of dasatinib on male and female fertility are not known. Men and women should use adequate contraception while receiving dasatinib. Talk to your doctor about what forms of contraception would be adequate.
Fluid retention: This medication can cause serious fluid retention. Contact your doctor immediately if you experience swelling in your feet, ankles, lower legs, or hands; weight gain; or increasing shortness of breath. Your doctor will weigh and monitor you regularly for signs of fluid retention while you are taking this medication.
Grapefruit juice: Grapefruit juice can increase the blood levels of dasatinib and increase the risk of potentially serious side effects. Do not drink grapefruit juice while taking this medication.
Infection: As well as killing cancer cells, dasatinib can reduce the number of cells that fight infection in the body (white blood cells). If possible, avoid contact with people with contagious infections.
Tell your doctor immediately if you notice signs of an infection, such as fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness. Your doctor will do blood tests regularly to monitor the number of white blood cells in your blood and adjust the dose or temporarily stop it if your blood counts are too low.
Lactose: This medication contains lactose. If you have galactose intolerance, the Lapp lactase deficiency, or glucose-galactose malabsorption, do not take dasatinib.
Liver function: Liver problems such as inflammation and increased liver enzyme levels in the blood have occurred in people taking dasatinib. Your doctor may monitor your liver function regularly while taking this medication. If you have decreased liver function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Pulmonary hypertension: There have been rare reports of pulmonary hypertension. Pulmonary hypertension is an increased blood pressure in the pulmonary arteries, the blood vessels that carry blood from the heart to the lungs. If you experience shortness of breath and fatigue, contact your doctor as soon as possible. If you have a heart problem or lung disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Pregnancy: This medication should not be used during pregnancy or by women who are planning to become pregnant. If it is taken by a woman who is pregnant, it may harm the developing baby. Women should avoid becoming pregnant while taking dasatinib. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if dasatinib passes into breast milk. Due to the potential for serious harm to a baby if they are exposed to this medication, breast-feeding must be stopped before starting this medication.
Children: The safety and effectiveness of using this medication have not been established for children less than 18 years of age.
Seniors: People over the age of 65 years may be more at risk of side effects from this medication.