This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
- An unsafe heartbeat that is not normal (long QT on ECG) has happened with this drug. Sudden deaths have rarely happened in people taking this drug. Talk with the doctor.
- This drug must only be used when other drugs cannot be used or have not worked. Talk with your doctor to be sure that the benefits of this drug are more than the risks.
- There is a higher chance of death in older adults who take this drug for mental problems caused by dementia. Most of the deaths were linked to heart disease or infection. This drug is not approved to treat mental problems caused by dementia.
- It is used to treat schizophrenia.
- It may be given to you for other reasons. Talk with the doctor.
- If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have heart problems.
- If you have ever had a long QT on ECG or other heartbeat that is not normal.
- If you have low potassium levels, talk with your doctor.
- If you are very sleepy.
- If you have recently drunk a lot of alcohol or taken a big amount of drugs that may slow your actions like phenobarbital or some pain drugs like oxycodone.
- If you are taking any of these drugs: Fluoxetine, fluvoxamine, paroxetine, pindolol, or propranolol.
- If you are taking any drugs that can cause a certain type of heartbeat that is not normal (prolonged QT interval). There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
This is not a list of all drugs or health problems that interact with this drug.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- Avoid driving and doing other tasks or actions that call for you to be alert until you see how this drug affects you.
- To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.
- Talk with your doctor before you drink alcohol or use other drugs and natural products that slow your actions.
- Low white blood cell counts have happened with drugs like this one. This may lead to a higher chance of infection. Rarely, infections have been deadly. Tell your doctor if you have ever had a low white blood cell count. Call your doctor right away if you have signs of infection like fever, chills, or sore throat.
- You will need an ECG before starting this drug and during treatment. Talk with your doctor.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- Be careful in hot weather or while being active. Drink lots of fluids to stop fluid loss.
- Dizziness, sleepiness, and feeling less stable may happen with this drug. These may lead to falling, which can cause broken bones or other health problems.
- If you will be near phosphorous insecticides, talk with your doctor.
- If you are 65 or older, use this drug with care. You could have more side effects.
- Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
- Taking this drug in the third trimester of pregnancy may lead to uncontrolled muscle movements and withdrawal in the newborn.
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Trouble controlling body movements, twitching, change in balance, trouble swallowing or speaking.
- Shakiness, trouble moving around, or stiffness.
- Dizziness or passing out.
- Fast or abnormal heartbeat.
- Chest pain or pressure.
- Feeling confused.
- Mood changes.
- Swelling in the arms or legs.
- Change in eyesight.
- Feeling very tired or weak.
- Pale skin.
- Ejaculation problems.
- Enlarged breasts, nipple discharge, not able to get or keep an erection (in males), or period (menstrual) changes (in females).
- Some people may get a severe muscle problem called tardive dyskinesia. This problem may lessen or go away after stopping this drug, but it may not go away. The risk is greater with diabetes and in older adults, especially older women. The risk is greater with longer use or higher doses, but it may also occur after short-term use with low doses. Call your doctor right away if you have trouble controlling body movements or problems with your tongue, face, mouth, or jaw like tongue sticking out, puffing cheeks, mouth puckering, or chewing.
- A very bad and sometimes deadly health problem called neuroleptic malignant syndrome (NMS) may happen. Call your doctor right away if you have any fever, muscle cramps or stiffness, dizziness, very bad headache, confusion, change in thinking, fast heartbeat, heartbeat that does not feel normal, or are sweating a lot.
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Diarrhea or constipation.
- Upset stomach or throwing up.
- Dry mouth.
- Feeling sleepy.
- Stuffy nose.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Keep taking this drug as you have been told by your doctor or other health care provider, even if you feel well.
- Take a missed dose as soon as you think about it.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
- Store at room temperature protected from light. Store in a dry place. Do not store in a bathroom.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else’s drugs.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.
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