Before taking clozapine,
tell your doctor and pharmacist if you are allergic to clozapine, any other medications, or any of the ingredients in clozapine tablets. Ask your pharmacist for a list of the ingredients.
tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention those listed in the IMPORTANT WARNING section and any of the following: antihistamines; cimetidine (Tagamet); antibiotics such as ciprofloxacin (Cipro) and erythromycin (E.E.S., E-Mycin, others); bupropion (Aplenzin, Wellbutrin, Zyban, in Contrave); escitalopram (Lexapro); medications for high blood pressure, mental illness, or nausea; medications for irregular heartbeat such as encainide, flecainide, propafenone (Rythmol), and quinidine (in Nuedexta); oral contraceptives; medications for seizures such as carbamazepine (Equetro, Tegretol, Teril, others) or phenytoin (Dilantin, Phenytek); rifampin (Rifadin, Rimactane, in Rifamate, in Rifater); sedatives; selective serotonin reuptake inhibitors (SSRIs) such as duloxetine (Cymbalta), fluoxetine (Prozac, Sarafem, Selfemra, others), fluvoxamine (Luvox), paroxetine (Brisdelle, Paxil, Pexeva), and sertraline (Zoloft); sleeping pills; terbinafine (Lamisil); and tranquilizers. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
tell your doctor what herbal products you are taking, especially St. John's wort.
in addition to the condition listed in the IMPORTANT WARNING section, tell your doctor if you or anyone in your family has ever had a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death); or if you have or have ever had problems with your urinary system or prostate (a male reproductive gland); dyslipidemia (high cholesterol levels); paralytic ileus (condition in which food cannot move through the intestine); glaucoma; high or low blood pressure; trouble keeping your balance; or heart, kidney, lung, or liver disease; or if you or anyone in your family has or has ever had diabetes. Also tell your doctor if you have ever had to stop taking a medication for mental illness because of severe side effects.
tell your doctor if you are pregnant, especially if you are in the last few months of your pregnancy, or if you plan to become pregnant or are breastfeeding. If you become pregnant while taking clozapine, call your doctor. Clozapine may cause problems in newborns following delivery if it is taken during the last months of pregnancy.
if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking clozapine.
you should know that alcohol can add to the drowsiness caused by this medication.
tell your doctor if you use tobacco products. Cigarette smoking may decrease the effectiveness of this medication.
you should know that you may experience hyperglycemia (increases in your blood sugar) while you are taking this medication, even if you do not already have diabetes. If you have schizophrenia, you are more likely to develop diabetes than people who do not have schizophrenia, and taking clozapine or similar medications may increase this risk. Tell your doctor immediately if you have any of the following symptoms while you are taking clozapine: extreme thirst, frequent urination, extreme hunger, blurred vision, or weakness. It is very important to call your doctor as soon as you have any of these symptoms, because high blood sugar can cause a serious condition called ketoacidosis. Ketoacidosis may become life-threatening if it is not treated at an early stage. Symptoms of ketoacidosis include: dry mouth, nausea and vomiting, shortness of breath, breath that smells fruity, and decreased consciousness.
if you have phenylketonuria (PKU, an inherited condition in which a special diet must be followed to prevent mental retardation), you should know that the orally disintegrating tablets contain aspartame that forms phenylalanine.