Thioridazine is a topic covered in the Consumer DrugInfo.

To view the entire topic, please or purchase a subscription.

Explore these free sample topics:

-- The first section of this topic is shown below --


(thye oh rid' a zeen)

Brand name:

  • Mellaril®

Important Warning

For all patients:

Thioridazine can cause a serious type of irregular heartbeat that may cause sudden death. There are other medications that can be used to treat your condition that are less likely to cause this life-threatening side effect. Therefore, you should not take thioridazine unless you have already been treated with at least 2 other medications for your condition and these medications did not work well or caused side effects that you could not tolerate.

Tell your doctor if you have or have ever had long QT syndrome (condition that increases the risk of developing an irregular heartbeat that may cause loss of consciousness or sudden death), a slow or irregular heartbeat, high or low blood pressure, heart disease, or a low level of potassium in your blood. Also tell your doctor if you are taking or plan to take any of the following medications: amiodarone (Cordarone), cisapride (Propulsid) (not available in the US), disopyramide (Norpace), dofetilide (Tikosyn), erythromycin (E.E.S., E-Mycin, Erythrocin), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), moxifloxacin (Avelox), paroxetine (Paxil, Pexeva), pimozide (Orap), pindolol (Visken), procainamide, propranolol (Inderal), quinidine, sotalol (Betapace, Betapace AF), and sparfloxacin (Zagam) (not available in the US). Your doctor will probably tell you not to take thioridazine if you are taking any of these medications or if you have any of these conditions.

In addition to the medications listed above, there are other medications that may increase the risk that thioridazine will cause you to develop a serious irregular heartbeat. Before you begin to take any new medication, tell the doctor who is prescribing the medication that you are taking thioridazine.

If you experience any of the following symptoms, call your doctor immediately: fast, irregular, or pounding heartbeat; dizziness; lightheadedness; or fainting.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain laboratory tests and electrocardiograms (tests to measure the electrical activity of the heart) before and during your treatment with thioridazine, especially when your dose is changed.

Talk to your doctor about the risks of taking thioridazine.

For older adults:

Studies have shown that older adults with dementia (a brain disorder that affects the ability to remember, think clearly, communicate, and perform daily activities and that may cause changes in mood and personality) who take antipsychotics (medications for mental illness) such as thioridazine have an increased chance of death during treatment.

Thioridazine is not approved by the Food and Drug Administration (FDA) for the treatment of behavior problems in older adults with dementia. Talk to the doctor who prescribed this medication if you, a family member, or someone you care for has dementia and is taking thioridazine. For more information, visit the FDA website:

-- To view the remaining sections of this topic, please or purchase a subscription --


* When formatting your citation, note that all book, journal, and database titles should be italicized* Article titles in AMA citation format should be in sentence-case
TY - ELEC T1 - Thioridazine ID - 112395 BT - Consumer DrugInfo UR - PB - American Society of Health System Pharmacists DP - Unbound Medicine ER -