Follow Us

Methsuximide

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Rare

  • Attempts at killing oneself
  • Feeling that others are watching you or controlling your behavior
  • Feeling that others can hear your thoughts
  • Feeling, seeing, or hearing things that are not there
  • Severe mood or mental changes
  • Unusual behavior

Incidence not known

  • Attack, assault, or force
  • Blistering, peeling, or loosening of the skin
  • Blood in the urine
  • Bloody, black, or tarry stools
  • Chest pain
  • Chills
  • Cloudy urine
  • Cough or hoarseness
  • Diarrhea
  • Discouragement
  • Feeling sad or empty
  • Fever
  • High fever
  • Irritability
  • Itching
  • Joint or muscle pain
  • Lack of appetite
  • Loss of interest or pleasure
  • Lower back or side pain
  • Mood or mental changes
  • Nervousness
  • Painful or difficult urination
  • Pale skin
  • Red skin lesions, often with a purple center
  • Red, irritated eyes
  • Shakiness and unsteady walk
  • Shortness of breath
  • Sore throat
  • Sores, ulcers, or white spots on the lips or in the mouth
  • Swelling around the eyes
  • Swollen glands
  • Tiredness
  • Trouble with concentrating
  • Trouble with sleeping
  • Unexplained bleeding or bruising
  • Unsteadiness, trembling, or other problems with muscle control or coordination
  • Unusual bleeding or bruising
  • Unusual tiredness or weakness
  • Vision changes

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

  • Change in consciousness
  • Difficult or troubled breathing
  • Irregular, fast or slow, or shallow breathing
  • Loss of consciousness
  • Pale or blue lips, fingernails, or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

  • Blurred vision
  • Change in color vision
  • Difficulty having a bowel movement (stool)
  • Difficulty seeing at night
  • Dizziness
  • Drowsiness
  • Heartburn
  • Hiccups
  • Hives or welts
  • Increased sensitivity of the eyes to sunlight
  • Loss of appetite
  • Nausea or vomiting
  • Pain or discomfort in the chest, upper stomach, or throat
  • Redness of the skin
  • Skin rash
  • Sleeplessness
  • Unable to sleep
  • Weight loss

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

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

Precautions

It is very important that your doctor check your progress at regular visits while you are using this medicine to see if it is working properly and to allow for a change in the dose. Blood and urine tests may be needed to check for any unwanted effects.

It is important to tell your doctor if you become pregnant while using this medicine. Your doctor may want you to join a pregnancy registry for patients taking a seizure medicine.

For some children, teenagers, and young adults, this medicine can increase thoughts of suicide. Tell your doctor or your child’s doctor right away if you or your child start to feel more depressed or have thoughts about hurting yourself. Report any unusual thoughts or behaviors that trouble you or your child, especially if they are new or get worse quickly. Make sure the doctor knows if you or your child have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. Also tell the doctor if you or your child have sudden or strong feelings, such as feeling nervous, angry, restless, violent, or scared. Let the doctor know if you, your child, or anyone in your family has bipolar disorder (manic-depressive) or has tried to commit suicide.

Do not stop taking this medicine without first checking with your doctor. Your doctor may want you or your child to gradually reduce the amount you are using before stopping completely.

Tell your doctor right away if you or your child feels unusually weak, starts bruising easily, has bleeding gums or nosebleeds, seems to be sick more often, has a fever, swollen glands, or a sore throat that will not go away. These could be a signs of a serious problem with the number of blood cells in your body.

Tell your doctor right away if you or your child has a skin rash, muscle or joint pain, feels unusually tired, has a low-grade fever, or pain the chest that gets worse with breathing. These could be signs of a serious condition called systematic lupus erythematosus (SLE).

Call your doctor right away if you or your child start to have a persistent cough, weight loss, night sweats, fever, chills, or flu-like symptoms such as a runny or stuffy nose, headache, blurred vision, or feeling generally ill. These may be signs that you have an infection.

Methsuximide may cause some people to become dizzy, drowsy, or less alert than they are normally. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or not alert.

Proper Use

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

If you notice that your capsules are not full or the contents have melted, call your pharmacist right away. The medicine may not work properly and should not be used.

This medicine may be used with other seizure medicines. Keep using all of your seizure medicines unless your doctor tells you to stop.

This medicine comes with a Medication Guide. It is very important that you read and understand this information. Be sure to ask your doctor about anything you do not understand.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor’s orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (capsules):
    • For seizures:
      • Adults, teenagers, and children—At first, 300 milligrams (mg) once a day. Your doctor may increase your dose if needed.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

This medicine melts easily, so do not store it in a place that is very hot (e.g., closed cars, delivery vans, or near steam pipes).

Description

Methsuximide is used to control absence (petit mal) seizures in the treatment of epilepsy. It is used after other medicines have been tried, but are unable to control the seizures. This medicine is an anticonvulsant that works in the brain tissue to stop seizures.

This medicine is available only with your doctor’s prescription.