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Thioridazine concentrate

Pronunciation

Generic Name: thioridazine (thye-oh-RID-a-zeen)
Brand Name: Generic only. No brands available.

Thioridazine concentrate may increase your risk of severe irregular heartbeat or sudden death. Thioridazine concentrate should only be used in patients who have not shown improvement with or are unable to take other medicines.


Thioridazine concentrate 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 concentrate is a phenothiazine. It is not known exactly how it works.

Do NOT use thioridazine concentrate if:

  • you are allergic to any ingredient in thioridazine concentrate or similar medicines (eg, phenothiazines)
  • you have a decreased level of consciousness, severe high or low blood pressure, low levels of potassium in the blood, abnormal heart function test (ECG), or a history of certain heart problems (eg, irregular heartbeat, congenital long QT syndrome)
  • you have a genetic problem that leads to decreased levels of the P-450 2D6 isozyme in your body
  • you are taking antiarrhythmics (eg, amiodarone, quinidine), cisapride, dofetilide, H1 antagonists (eg, astemizole, terfenadine), pergolide, pindolol, propranolol, sparfloxacin, selective serotonin reuptake inhibitor (SSRI) antidepressants (eg, fluoxetine, paroxetine, fluvoxamine), streptogramins (eg, dalfopristin), or medicines that may affect your heartbeat. Ask your doctor or pharmacist if you are unsure if any of your medicines may affect your heartbeat
  • you are taking disulfiram or metronidazole, or you have taken fluorouracil within the past 7 days

Contact your doctor or health care provider right away if any of these apply to you.

Before using thioridazine concentrate:

Some medical conditions may interact with thioridazine concentrate. 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 a history of heart problems (eg, slow heartbeat), high or low blood pressure, blood problems (eg, porphyria), bone marrow problems (eg, low blood platelet levels, low white blood cell count), liver problems (eg, cirrhosis), kidney problems, enlarged prostate gland, seizures or epilepsy, Parkinson disease, Reye syndrome, or a history of breast cancer
  • if you have increased pressure in the eyes or glaucoma, or if you are at risk for glaucoma
  • if you are regularly exposed to extreme heat or phosphorus insecticides
  • if you have a history of alcohol abuse or if you drink more than 3 alcohol-containing drinks per day

Some MEDICINES MAY INTERACT with thioridazine concentrate. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Anticholinergics (eg, atropine) because they may decrease the effectiveness of thioridazine concentrate
  • Antiarrhythmics (eg, amiodarone, quinidine), arsenic, beta blockers (eg, propranolol), cisapride, dofetilide, droperidol, H1 antagonists (eg, astemizole, terfenadine ), haloperidol, ketolides (eg, telithromycin), macrolide antibiotics (eg, erythromycin), pimozide, pindolol, quinolones (eg, sparfloxacin, levofloxacin), serotonin norepinephrine reuptake inhibitors (eg, duloxetine), serotonin receptor antagonist antiemetics (eg, dolasetron), SSRI antidepressants (eg, fluoxetine, paroxetine, fluvoxamine), streptogramins (eg, dalfopristin), ziprasidone, or other medicines that may affect your heartbeat because risk of severe and possibly fatal side effects, including severe irregular heartbeat, may be increased. Ask your doctor or pharmacist if you are unsure if any of your medicines may affect your heartbeat.
  • Disulfiram , fluorouracil, or metronidazole because the risk of side effects, including headache, fast or irregular heartbeat, nausea, vomiting, and trouble breathing, may be increased
  • Atropine, barbiturates (eg, phenobarbital), narcotics (eg, codeine), or tricyclic antidepressants (eg, amitriptyline) because risk of side effects may be increased by thioridazine concentrate
  • Guanethidine, levodopa, or pergolide because their effectiveness may be decreased by thioridazine concentrate

This may not be a complete list of all interactions that may occur. Ask your health care provider if thioridazine concentrate 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 concentrate:

Use thioridazine concentrate as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Thioridazine concentrate may be taken with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
  • Use the dropper that comes with thioridazine concentrate to measure your dose. Ask your pharmacist for help if you are unsure of how to measure your dose.
  • Thioridazine concentrate may be mixed with distilled water, acidified tap water, or juice just before you take it. Be sure to take your entire dose. Do not store any mixed medicine for use at a future time.
  • Continue to use thioridazine concentrate even if you feel well. Do not miss any doses.
  • If you miss a dose of thioridazine concentrate, 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 concentrate.

Important safety information:

  • Thioridazine concentrate 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 concentrate. Using thioridazine concentrate alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.
  • Avoid drinking alcohol or taking other medications that cause drowsiness (eg, sedatives, tranquilizers) while taking thioridazine concentrate. Thioridazine concentrate will add to the effects of alcohol and other depressants. Ask your pharmacist if you have questions about which medicines are depressants.
  • Alcohol, hot weather, exercise, and fever can increase the risk of dizziness, lightheadedness, or fainting. To prevent these effects, sit up or stand slowly, especially in the morning. Also, sit or lie down at the first sign of dizziness, lightheadedness, or weakness.
  • Do not become overheated in hot weather or during exercise or other activities because heatstroke may occur.
  • Involuntary and uncontrollable movements may develop with use of thioridazine concentrate. Occurrence is highest among the elderly, especially women. The risk of developing these involuntary movements and the likelihood they will become permanent are increased with long-term use and with high doses. However, it is possible to develop these symptoms after short-term treatment at low doses. Contact your doctor at once if any of the following occur: involuntary movements of tongue, face, mouth, or jaw (eg, sticking out of the tongue, puffing of cheeks, puckering of mouth, chewing movements), or involuntary movements of the arms and legs.
  • Neuroleptic malignant syndrome (NMS) is a serious side effect associated with thioridazine concentrate. Symptoms include increased body heat; muscle rigidness; altered mental abilities, including lack of response to your surroundings; irregular or fast heartbeat; or sweating. Contact your doctor at once if any of these symptoms occur.
  • Before you have any medical or dental treatments, emergency care, or surgery, tell the doctor or dentist that you are using thioridazine concentrate.
  • Thioridazine concentrate may cause false results in some pregnancy tests. Check with your doctor if you have any questions or concerns. Make sure your doctor and laboratory personnel know you are using thioridazine concentrate.
  • LAB TESTS, including heart function tests and blood potassium levels,, may be performed to monitor your progress or to check for side effects. Be sure to keep all doctor and lab appointments.
  • Use thioridazine concentrate with caution in the ELDERLY because they may be more sensitive to its effects, especially dizziness, lightheadedness (especially upon standing), involuntary muscle movements, and blood problems (low white blood cell levels).
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using thioridazine concentrate during pregnancy. Thioridazine concentrate is excreted in breast milk. Do not breast-feed while taking thioridazine concentrate.

If you suddenly stop taking thioridazine concentrate, especially if you have been taking high doses, you may experience WITHDRAWAL symptoms, including nausea, vomiting, dizziness, and tremors.

Possible side effects of thioridazine concentrate:

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:

Agitation; bizarre dreams; constipation; diarrhea; dizziness; drowsiness; dry mouth; loss of appetite; nausea; stuffy nose; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); changes in menstrual period; changes in sexual ability; chest pain; confusion; dark urine; difficulty swallowing; drooling; fainting; fast, slow, or irregular heartbeat; fever, chills, or sore throat; hyperactivity; involuntary movements or spasms of the arms, legs, tongue, face, mouth, or jaw; mask-like face; muscle restlessness; restlessness; seizures; severe or persistent dizziness; severe constipation; shuffling walk; sleeplessness; sore mouth or gums; stiff or rigid muscles; stomach pain; sweating; swelling of the hands or feet; trouble urinating; unusual bruising or bleeding; unusual eye movements or inability to move eyes; unusual mood or mental changes, including lack of response to your surroundings; vision changes; weakness of arms or legs; yellowing of the skin or eyes.

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 deep sleep or loss of consciousness; fast, slow, or irregular heartbeat; muscle spasms; restlessness; seizures; severe drowsiness; shortness of breath; tremors; trouble urinating; twitching.

Proper storage of thioridazine concentrate:

Store thioridazine concentrate at room temperature, below 86 degrees F (30 degrees C), in a tightly closed container. Store away from heat, moisture, and light. Do not store in the bathroom. Keep thioridazine concentrate out of the reach of children and away from pets.

General information:

  • If you have any questions about thioridazine concentrate, please talk with your doctor, pharmacist, or other health care provider.
  • Thioridazine concentrate 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 concentrate 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 is a summary only. It does not contain all information about thioridazine concentrate. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

Review Date: November 3, 2016

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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