SIDE EFFECTS: Diarrhea, nausea, vomiting, abdominal pain, loss of appetite, heartburn, constipation, or tiredness may occur. Nausea and vomiting can be severe. In some cases, your doctor may prescribe medication to prevent or relieve nausea, vomiting, or diarrhea. Eating several small meals, not eating before treatment, or limiting activity may help lessen some of these effects. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. People using this medication may have serious side effects. However, your doctor has prescribed this drug because he or she has judged that the benefit to you is greater than the risk of side effects. Careful monitoring by your doctor may decrease your risk. Tell your doctor right away if you have any serious side effects, including: numbness/tingling, symptoms of liver problems (such as nausea/vomiting that doesn't stop, loss of appetite, stomach/abdominal pain, yellowing eyes/skin, dark urine), vision changes (such as blurred vision, decreased vision), weakness. Get medical help right away if you have any very serious side effects, including: trouble breathing, cough with or without phlegm, fast/slow/irregular heartbeat, severe dizziness, fainting, seizure. This medication may rarely make your blood sugar rise, which can cause or worsen diabetes. Tell your doctor right away if you have symptoms of high blood sugar such as increased thirst/urination. If you already have diabetes, check your blood sugar regularly as directed and share the results with your doctor. Your doctor may need to adjust your diabetes medication, exercise program, or diet. Persistent vomiting/diarrhea may result in a serious loss of body water (dehydration). Contact your doctor promptly if you notice any symptoms of dehydration, such as unusual decreased urination, unusual dry mouth/thirst, fast heartbeat, or dizziness/lightheadedness. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. Ceritinib can commonly cause a rash that is usually not serious. However, you may not be able to tell it apart from a rare rash that could be a sign of a severe reaction. Therefore, tell your doctor right away if you develop any rash. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch. In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking this medication, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details. Before using this medication, tell your doctor or pharmacist your medical history, especially of: diabetes or high blood sugar, liver problems. Ceritinib may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away. The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using ceritinib, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death). Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using ceritinib safely. This drug may rarely cause vision changes. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Limit alcoholic beverages. Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above). Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the capsules. This medication is not recommended for use during pregnancy. It may harm an unborn baby. Consult your doctor for more details and to discuss using reliable forms of birth control (such as condoms, birth control pills) while using this medication. Women of childbearing age should continue using reliable forms of birth control for 6 months after stopping treatment. Men with female partners of childbearing age should continue using condoms for 3 months after stopping treatment. If you or your partner become pregnant or think you may be pregnant, tell your doctor right away. It is unknown if this medication passes into breast milk. Because of the possible risk to the infant, breast-feeding while using this drug is not recommended and for 2 weeks after stopping treatment. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: See also How to Use section. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval. Some products that may interact with this drug include: other drugs that may slow the heartbeat (including digoxin, clonidine, beta-blockers such as atenolol/metoprolol, calcium channel blockers such as diltiazem/verapamil). Other medications can affect the removal of ceritinib from your body, which may affect how ceritinib works. Examples include azole antifungals (such as itraconazole, ketoconazole), macrolide antibiotics (such as erythromycin), rifamycins (such as rifampin, rifabutin), drugs for seizures (such as carbamazepine, phenytoin), St. John's wort, among others. This medication can slow down the removal of other medications from your body, which may affect how they work. Examples include alfentanil, ergots (such as ergotamine), fentanyl, tacrolimus, among others.

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.