Generic Name: thioridazine (THYE-oh-RID-a-zeen)
Brand Name: Generic only. No brands available.
Thioridazine may increase your risk of severe and possibly fatal irregular heartbeat. Thioridazine should only be used in patients who have not shown improvement with or are unable to take other medicines.
Thioridazine is an antipsychotic. It may increase the risk of death when used to treat mental problems caused by dementia in elderly patients. Most of the deaths were linked to heart problems or infection. Thioridazine is not approved to treat mental problems caused by dementia. Discuss any questions or concerns with your doctor.
Thioridazine is used for:
Treating schizophrenia in patients who have not shown improvement with or are unable to take other medicines. It may also be used for other conditions as determined by your doctor.
Thioridazine is a phenothiazine. It is not known exactly how it works.
Do NOT use thioridazine if:
- you are allergic to any ingredient in thioridazine or to other phenothiazines (eg, chlorpromazine)
- you have a certain type of irregular heartbeat (congenital long QT syndrome, prolonged QT interval) or a history of other types of irregular heartbeat
- you have severe drowsiness, severe high or low blood pressure, or low levels of potassium in the blood
- you have recently taken large amounts of alcohol or medicines that may cause drowsiness, such as barbiturates (eg, phenobarbital) or narcotic pain medicines (eg, codeine)
- you are taking certain antiarrhythmics (eg, amiodarone, bretylium, quinidine, sotalol), astemizole, cabergoline, cisapride, dofetilide, metoclopramide, pergolide, pindolol, propranolol, certain selective serotonin reuptake inhibitors (SSRIs) (eg, fluoxetine, paroxetine, fluvoxamine), terfenadine, tramadol, or any medicine that may increase the risk of a certain type of irregular heartbeat (prolonged QT interval). Ask your doctor or pharmacist if you are unsure if any of your medicines may increase the risk of this type of irregular heartbeat
Contact your doctor or health care provider right away if any of these apply to you.
Before using thioridazine:
Some medical conditions may interact with thioridazine. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have developed severe side effects (eg, blood problems, yellowing of the skin or eyes) while taking another phenothiazine (eg, chlorpromazine)
- if you have a history of heart problems (eg, angina, mitral valve problems, slow heartbeat), high or low blood pressure, blood problems (eg, anemia, porphyria), bone marrow problems (eg, low white blood cell count), diabetes, liver problems (eg, cirrhosis), kidney problems, neuroleptic malignant syndrome (NMS), tardive dyskinesia (TD), an enlarged prostate gland, seizures, trouble urinating, mental or mood problems (eg, depression), or an adrenal gland tumor (pheochromocytoma)
- if you have asthma, a lung infection, or other lung or breathing problems (eg, emphysema); or increased pressure in the eyes or glaucoma or if you are at risk of glaucoma
- if you have Alzheimer disease, dementia, Parkinson disease, or Reye syndrome
- if you have had high blood prolactin levels, a history of certain types of cancer (eg, breast, pancreas, pituitary, brain), or if you are at risk of breast cancer
- if you are in poor health or are regularly exposed to extreme heat or certain insecticides (organophosphorus insecticides)
- if you have a history of alcohol abuse, drink alcohol, or are in alcohol withdrawal
Some MEDICINES MAY INTERACT with thioridazine. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Many prescription and nonprescription medicines (eg, used for allergies, blood clotting problems, cancer, infections, inflammation, aches and pains, heart problems, high blood pressure, high cholesterol, irregular heartbeat, mental or mood problems, nausea or vomiting, Parkinson disease, seizures, stomach or bowel problems, overactive bladder), multivitamin products, and herbal or dietary supplements (eg, herbal teas, coenzyme Q10, garlic, ginseng, gingko, St. John's wort) may interact with thioridazine. Ask your doctor if you are unsure if any of your medicines may interact with thioridazine
This may not be a complete list of all interactions that may occur. Ask your health care provider if thioridazine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use thioridazine:
Use thioridazine as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Thioridazine may be taken with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
- Continue to use thioridazine even if you feel well. Do not miss any doses.
- If you miss a dose of thioridazine, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use thioridazine.
Important safety information:
- Thioridazine may cause drowsiness, dizziness, or blurred vision. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to thioridazine. Using thioridazine alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.
- Thioridazine may cause dizziness, light-headedness, or fainting; alcohol, hot weather, exercise, or fever may increase these effects. To prevent them, sit up or stand slowly, especially in the morning. Sit or lie down at the first sign of any of these effects.
- Do NOT take more than the recommended dose without checking with your doctor.
- Do not drink alcohol while you are using thioridazine.
- Check with your doctor before you use medicines that may cause drowsiness (eg, sleep aids, muscle relaxers) while you are using thioridazine; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
- Do not become overheated in hot weather or while you are being active; heatstroke may occur.
- Thioridazine may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how your react to thioridazine. Use a sunscreen or wear protective clothing if you must be outside for more than a short time.
- Thioridazine may lower the ability of your body to fight infection. Avoid contact with people who have colds or infections. Tell your doctor if you notice signs of infection like fever, sore throat, rash, or chills.
- Some patients who take thioridazine may develop muscle movements that they cannot control. This is more likely to happen in elderly patients, especially women. The chance that this will happen or that it will become permanent is greater in those who take thioridazine in higher doses or for a long time. Muscle problems may also occur after short-term treatment with low doses. Tell your doctor at once if you have muscle problems with your arms; legs; or your tongue, face, mouth, or jaw (eg, tongue sticking out, puffing of cheeks, mouth puckering, chewing movements) while taking thioridazine.
- NMS is a possibly fatal syndrome that can be caused by thioridazine. Symptoms may include fever; stiff muscles; confusion; abnormal thinking; fast or irregular heartbeat; and sweating. Contact your doctor at once if any of these symptoms occur.
- Thioridazine may increase the amount of a certain hormone (prolactin) in your blood. Symptoms may include enlarged breasts, missed menstrual period, decreased sexual ability, or nipple discharge. Contact your doctor right away if you experience any of these symptoms.
- Tell your doctor or dentist that you take thioridazine before you receive any medical or dental care, emergency care, or surgery.
- Diabetes patients - Thioridazine may affect your blood sugar. Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.
- Thioridazine may cause the results of some pregnancy tests to be wrong. Check with your doctor if you have any questions or concerns about your pregnancy test results.
- Thioridazine may interfere with certain lab tests. Make sure your doctor and laboratory personnel know you are using thioridazine.
- Lab tests, including liver and kidney function, complete blood cell counts, heart function, and blood potassium levels, may be performed while you use thioridazine. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- Use thioridazine with caution in the ELDERLY because they may be more sensitive to its effects, especially confusion; constipation; dizziness or light-headedness, especially upon standing; drowsiness; fainting; trouble urinating; and uncontrolled muscle movements.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using thioridazine during pregnancy. Using thioridazine during the third trimester may result in uncontrolled muscle movements or withdrawal symptoms in the newborn. Discuss any questions or concerns with your doctor. Thioridazine is excreted in breast milk. Do not breast-feed while taking thioridazine.
If you suddenly stop taking thioridazine, you may experience WITHDRAWAL symptoms, including nausea, vomiting, dizziness, stomach upset, and tremors.
Possible side effects of thioridazine:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Agitation; constipation; diarrhea; dizziness; drowsiness; dry mouth; enlarged pupils; jitteriness; nausea; stuffy nose; vomiting.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest or throat; swelling of the mouth, face, lips, or tongue; unusual hoarseness; wheezing); chest pain; confusion; decreased coordination; drooling; fainting; fast, slow, or irregular heartbeat; mask-like face; muscle spasms of the face, neck, or back; muscle weakness; new or worsening mental or mood problems; numbness of an arm or leg; prolonged or painful erection; restlessness; seizures; severe or persistent constipation; severe or persistent dizziness, drowsiness, or headache; shuffling walk; sleeplessness; stiff or rigid muscles; sudden shortness of breath or vomiting; swelling of the hands, ankles, or feet; symptoms of infection (eg, fever, chills, persistent sore throat); symptoms of liver problems (eg, yellowing of the skin or eyes; dark urine; pale stools; severe or persistent nausea, stomach pain, or loss of appetite); tremor; trouble urinating; twisting or twitching movements; uncontrolled muscle movements (eg, twitching of the face or tongue; loss of balance; uncontrolled movements of arms or legs; trouble speaking, breathing, or swallowing); unusual bruising or bleeding; unusual eye movements or inability to move eyes; unusual or excessive sweating; unusual tiredness or weakness; unusually pale skin; vision changes (eg, blurred vision).
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include agitation; coma; confusion; difficulty breathing; fainting; fast, slow, or irregular heartbeat; loss of consciousness; muscle spasms or uncontrolled muscle movements; restlessness; seizures; severe constipation or stomach pain; severe drowsiness or dizziness; tremors; or trouble urinating.Proper storage of thioridazine:
Store thioridazine at room temperature, between 68 and 77 degrees F (20 and 25 degrees C), in a tightly closed container. Store away from heat, moisture, and light. Do not store in the bathroom. Keep thioridazine out of the reach of children and away from pets.
- If you have any questions about thioridazine, please talk with your doctor, pharmacist, or other health care provider.
- Thioridazine is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- If using thioridazine for an extended period of time, obtain refills before your supply runs out.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take thioridazine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. 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 thioridazine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to thioridazine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using thioridazine.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. 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 your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.
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- Other brands: Mellaril