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Trimethadione (By mouth)

Trimethadione (trye-meth-a-DYE-one)

Controls seizures.

Brand Name(s):

When This Medicine Should Not Be Used:

How to Use This Medicine:

Chewable Tablet

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• You may chew this tablet or swallow it whole.
• This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store this medicine in a closed container inside the refrigerator. Keep it tightly closed.
• Drop off any unused narcotic medicine at a drug take-back location right away. If you do not have a drug take-back location near you, flush any unused narcotic medicine down the toilet. Check your local drug store and clinics for take-back locations. You can also check the DEA web site for locations. Here is the link to the FDA safe disposal of medicines website: www.fda.gov/drugs/resourcesforyou/consumers/buyingusingmedicinesafely/ensuringsafeuseofmedicine/safedisposalofmedicines/ucm186187.htm

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Tell your doctor knows if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, any blood disorder, eye problems, or a history of depression.
• This medicine may cause the following problems:
  • Low blood cell counts, which may cause bleeding problems or increase your risk for infection
  • Serious skin reactions
  • Liver problems
  • Kidney problems
  • Eye or vision problems
  • Lupus-like or myasthenia-like syndrome
• This medicine can increase depression or thoughts of suicide. Tell your doctor right away if you start to feel more depressed and have thoughts about hurting yourself.
• Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.
• This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Blistering, peeling, red skin rash
• Blurred vision, changes in vision
• Change in how much or how often you urinate
• Dark urine or pale stools, loss of appetite, stomach pain, yellow skin or eyes
• Fever, chills, cough, sore throat, body aches
• Severe muscle weakness, swollen glands in your armpits, neck, or groin, chest pain, trouble breathing
• Thoughts of hurting yourself, unusual thoughts or behaviors
• Unusual bleeding, bruising, or weakness

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024