PRECAUTIONS: See also Warning and Side Effects sections.Before taking clozapine, 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.This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: history of blood disorders (e.g., leukemia, low white blood cell count), history of blood disorders caused by clozapine, serious bowel problems (e.g., paralytic ileus), seizures not controlled by medication.Before using this medication, tell your doctor or pharmacist your medical history, especially of: bowel problems (e.g., irritable bowel syndrome), breathing problems, diabetes/family history of diabetes, high cholesterol/triglyceride levels, glaucoma, heart problems, kidney problems, liver problems, obesity/family history of obesity, seizures, difficulty urinating (e.g., prostate problems).Clozapine may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can infrequently result in 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 affect the heart rhythm. Before using clozapine, 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 clozapine safely.This drug may make you dizzy or drowsy or cause blurred vision. 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.To minimize dizziness and lightheadedness, get up slowly when rising from a seated or lying position.Tell your doctor if you are a descendent of Ashkenazi Jews because you may be at a higher risk for a drop in your white blood cells.Before having surgery, tell your doctor or dentist that you are using this medication.The rapidly dissolving form of this drug may contain aspartame or phenylalanine. If you have phenylketonuria (PKU) or any other condition that requires you to restrict your intake of aspartame (or phenylalanine), consult your doctor or pharmacist about the safe use of this medicine.Older adults may be more sensitive to the side effects of this drug, especially constipation, dizziness, and QT prolongation (see above). Dizziness can increase the risk of falling.During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. Do not stop taking this medication unless directed by your doctor. Babies born to mothers who have used this drug during the last 3 months of pregnancy may infrequently develop symptoms including muscle stiffness or shakiness, drowsiness, feeding/breathing difficulties, or constant crying. If you notice any of these symptoms in your newborn anytime during their first month, tell the doctor right away.This medication may pass into breast milk and have undesirable effects on a nursing infant. Breast feeding is not recommended while taking clozapine. Consult your doctor before breast-feeding.
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