Generic Name: thioridazine (oral) (THYE oh RID a zeen)Brand Names: Mellaril, Mellaril-S
What is thioridazine?
Thioridazine is an anti-psychotic medication in a group of drugs called phenothiazines (FEEN-oh-THYE-a-zeens). It works by changing the actions of chemicals in your brain.
Thioridazine is used to treat psychotic disorders such as schizophrenia.
Thioridazine is usually given after other medications have been tried without successful treatment of schizophrenia.
Thioridazine may also be used for other purposes not listed in this medication guide.
What is the most important information I should know about thioridazine?
Stop using this medication and call your doctor at once if you have twitching or uncontrollable movements of your eyes, lips, tongue, face, arms, or legs. These could be early signs of dangerous side effects. Thioridazine is not for use in psychotic conditions related to dementia. Thioridazine may cause heart failure, sudden death, or pneumonia in older adults with dementia-related conditions. Do not use thioridazine if you have brain damage, bone marrow depression, severe heart disease, a heart rhythm disorder, a history of "Long QT syndrome," or if you are also using large amounts of alcohol or medicines that make you sleepy.
Do not take thioridazine together with large amounts of alcohol or medicines that make you sleepy, or with medications that can affect heart rhythm. There are many medicines that should not be taken together with thioridazine because they may cause serious medical problems. Before taking thioridazine, tell your doctor about all other medications you use.
Before you take thioridazine, tell your doctor if you have heart disease, high blood pressure, a heart rhythm disorder, low levels of calcium or potassium in your blood, past or present breast cancer, liver or kidney disease, severe asthma or breathing problems, a history of seizures, Parkinson's disease, adrenal gland tumor, enlarged prostate or urination problems, glaucoma, or if you have ever had a serious side effect while using thioridazine or a similar medication.
What should I discuss with my healthcare provider before taking thioridazine?
Thioridazine is not for use in psychotic conditions related to dementia. Thioridazine may cause heart failure, sudden death, or pneumonia in older adults with dementia-related conditions. Do not use thioridazine if you are allergic to thioridazine, or if you have brain damage, bone marrow depression, severe heart disease, a heart rhythm disorder, a history of "Long QT syndrome," or if you are also using large amounts of alcohol or medicines that make you sleepy.
There are many medicines that should not be taken together with thioridazine because they may cause serious medical problems. Tell your doctor about all other medications you take, including:
blood pressure medications;
medications to treat or prevent malaria;
certain HIV/AIDS medications;
migraine headache medicine;
heart rhythm medications;
medicine to prevent or treat nausea and vomiting;
certain narcotic pain medicines; and
other anti-psychotic medicines.
If you have certain conditions, you may need a dose adjustment or special tests to safely take thioridazine. Before you take this medication, tell your doctor if you have:
heart disease, high blood pressure, or a heart rhythm disorder;
low levels of potassium in your blood (hypokalemia);
past or present breast cancer;
- liver or kidney disease;
severe asthma, emphysema, or other breathing problem;
a history of seizures;
adrenal gland tumor (pheochromocytoma);
enlarged prostate or urination problems;
low levels of calcium in your blood (hypocalcemia);
if you have ever had a serious side effect while using thioridazine or another phenothiazine.
It is not known whether thioridazine is harmful to an unborn baby. Before taking this medication, tell your doctor if you are pregnant or plan to become pregnant during treatment. Thioridazine can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
How should I take thioridazine?
Take this medication exactly as prescribed by your doctor. Do not take it in larger amounts or for longer than recommended. Follow the directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results from this medication.
Your heart may need to be checked using an electrocardiograph or ECG (sometimes called an EKG) before you start taking thioridazine, or whenever your dose is changed. An ECG measures electrical activity of the heart. This will help your doctor determine whether the medication is causing any harmful effects. Do not miss any scheduled visits to your doctor while you are taking thioridazine.
Store thioridazine at room temperature away from moisture, heat, and light.
What happens if I miss a dose?
Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention if you think you have used too much of this medicine. Overdose symptoms may include dry mouth, constipation, bloating or stomach cramps, extreme dizziness, dry skin, blurred vision, decreased urination, uncontrollable muscle movements, confusion, agitation, feeling hot or cold, fast or pounding heartbeat, fainting, slow heart rate, weak or shallow breathing, and seizure (convulsions).
What should I avoid while taking thioridazine?
Thioridazine can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert. Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall. Avoid drinking alcohol. It can increase some of the side effects of thioridazine. Avoid exposure to sunlight or tanning beds. Thioridazine can make your skin more sensitive to sunlight, and a sunburn may result. Wear sunscreen (SPF 15 or higher) and protective clothing if you must be outdoors.
Thioridazine side effects
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Stop using thioridazine and call your doctor at once if you have a serious side effect such as:
dizziness, fainting, fast or pounding heartbeat;
twitching or uncontrollable movements of your eyes, lips, tongue, face, arms, or legs;
tremor (uncontrolled shaking), drooling, trouble swallowing, problems with balance or walking;
feeling restless, jittery, or agitated;
high fever, stiff muscles, confusion, sweating, fast or uneven heartbeats, rapid breathing;
feeling like you might pass out;
decreased night vision, tunnel vision, watery eyes, increased sensitivity to light;
pale skin, easy bruising or bleeding, fever, sore throat, flu symptoms;
urinating less than usual or not at all;
nausea and stomach pain, skin rash, and jaundice (yellowing of the skin or eyes);
joint pain or swelling with fever, swollen glands, muscle aches, chest pain, vomiting, unusual thoughts or behavior, and patchy skin color; or
slow heart rate, weak pulse, fainting, slow breathing (breathing may stop).
Less serious side effects may include:
dizziness, drowsiness, anxiety;
dry mouth, stuffy nose, constipation;
blurred vision, headache;
breast swelling or discharge;
changes in your menstrual periods;
weight gain, swelling in your hands or feet;
impotence, trouble having an orgasm;
increased or decreased interest in sex;
sleep problems (insomnia), strange dreams; or
mild itching or skin rash.
This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect thioridazine?
Cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression or anxiety can interact with thioridazine and cause medical problems or increase side effects. Tell your doctor if you regularly use any of these medicines, or any other anti-psychotic medications.
atropine (Atreza, Sal-Tropine);
lithium (Eskalith, Lithobid);
birth control pills or hormone replacement estrogens;
a blood thinner such as warfarin (Coumadin);
certain asthma medications or bronchodilators;
insulin or diabetes medications you take by mouth;
medication for nausea, vomiting, or motion sickness;
medications used for general anesthesia;
medicines used to prevent organ transplant rejection;
numbing medicine such as lidocaine or Novocain;
a stimulant or ADHD medication;
ulcer or irritable bowel medications; or
medicines to treat Parkinson's disease, restless leg syndrome, or pituitary gland tumor (prolactinoma).
There are many other medicines that can cause serious medical problems if you take them together with thioridazine. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor. Keep a list with you of all the medicines you use and show this list to any doctor or other healthcare provider who treats you.
Where can I get more information?
- Your pharmacist can provide more information about thioridazine.
- Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
- Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.
Copyright 1996-2006 Cerner Multum, Inc. Version: 9.02. Revision Date: 4/12/2009 4:37:19 PM.
- Thioridazine MedFacts Consumer Leaflet (Wolters Kluwer)
- Thioridazine Prescribing Information (FDA)
- Mellaril Detailed Consumer Information (PDR)