Ethosuximide (Oral)
Generic name: ethosuximide [ eth-oh-SUX-i-mide ]
Brand name: Zarontin
Drug class: Succinimide anticonvulsants
Medically reviewed by Drugs.com. Last updated on Dec 6, 2023.
Uses for ethosuximide
Ethosuximide is used to control absence (petit mal) seizures in patients with epilepsy. This medicine is an anticonvulsant that works in the brain tissue to stop seizures.
This medicine is available only with your doctor's prescription.
Before using ethosuximide
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Allergies
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Pediatric
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of ethosuximide in children. However, safety and efficacy have not been established in children younger than 3 years of age.
Geriatric
No information is available on the relationship of age to the effects of ethosuximide in geriatric patients.
Breast Feeding
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with Medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Calcifediol
- Fosphenytoin
- Orlistat
- Phenytoin
- Valproic Acid
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Ginkgo
- Nevirapine
- Phenobarbital
- Semaglutide
Interactions with Food/Tobacco/Alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Blood or bone marrow problems or
- Depression, history of or
- Kidney disease or
- Liver disease or
- Mental health problems, history of or
- Systematic lupus erythematosus (SLE)—Use with caution. May make these conditions worse.
Proper use of ethosuximide
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.
This medicine comes with a Medication Guide. Read and follow the instructions carefully. Ask your doctor if you have any questions.
This medicine can be used with other seizure medicines. Keep using all of your seizure medicines unless your doctor tells you to stop.
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 and children 6 years of age and older—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 500 milligrams (mg) once a day. Your doctor may increase your dose as needed.
- Children 3 to 6 years of age—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 250 mg once a day. Your doctor may increase your dose as needed.
- Children younger than 3 years of age—Use and dose must be determined by your doctor.
- For seizures:
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
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
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.
Related/similar drugs
Briviact, gabapentin, clonazepam, lamotrigine, pregabalin, lorazepam, topiramate, diazepam
Precautions while using ethosuximide
It is very important that your doctor check your progress closely while you or your child 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.
Do not stop taking this medicine without first checking with your doctor. Stopping the medicine suddenly may cause your seizures to return or to occur more often. Your doctor may want you or your child to gradually reduce the amount you are using before stopping completely.
This medicine may increase the chance of experiencing grand mal seizures in certain patients. Talk with your doctor if you have concerns about this risk.
Ethosuximide may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you, your child, or your caregiver notice any of these side effects, tell your doctor or your child's doctor right away.
This medicine may increase your risk of having systemic lupus erythematosus (SLE). Tell your doctor right away if you or your child has chest pain, fever and chills, general feeling of discomfort or illness, hair loss, headache, muscle or joint pain, skin rash, sore throat, swollen glands, or trouble breathing.
This medicine will lower the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.
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.
Call your doctor right away if you or your child start to have persistent cough, weight loss, night sweats, fever, chills, or flu-like symptoms such as runny or stuffy nose, headache, blurred vision, or feeling generally ill.
Serious skin reactions, including Stevens-Johnson syndrome and drug reactions with eosinophilia and systemic symptoms (DRESS) can occur with this medicine, which can be life-threatening. Check with your doctor right away if you have black, tarry stools, blistering, peeling, or loosening of the skin, chest pain, chills, cough, diarrhea, itching, joint or muscle pain, painful or difficult urination, red irritated eyes, red skin lesions, often with a purple center, sore throat, sores, ulcers, or white spots in the mouth or on the lips, swollen glands, unusual bleeding or bruising, or unusual tiredness or weakness while you or your child are using this medicine.
Ethosuximide may cause dizziness, drowsiness, 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 are not alert.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Side Effects of ethosuximide
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
- Changes in behavior
- discouragement
- feeling sad or empty
- irritability
- lack of appetite
- loss of interest or pleasure
- mood or mental changes
- thoughts of killing oneself
- tiredness
- trouble with concentrating
- trouble with sleeping
Incidence not known
- Bleeding gums
- blistering, peeling, or loosening of the skin
- blood in the urine
- bloody, black, or tarry stools
- chest pain
- cough or hoarseness
- diarrhea
- enlarged gums
- false or unusual sense of well-being
- fever with or without chills
- general feeling of discomfort or illness
- hair loss
- headaches
- high fever
- hives, itching, skin rash
- joint or muscle pain
- lower back or side pain
- nervousness
- not able to concentrate
- painful or difficult urination
- pale skin
- pinpoint red spots on the skin
- red skin lesions, often with a purple center
- red, irritated eyes
- restlessness
- shakiness and unsteady walk
- sore throat
- sores, ulcers, or white spots on the lips or in the mouth
- swelling around the eyes
- swelling of the tongue
- swollen, painful, or tender lymph glands in the neck, armpit, or groin
- trouble sitting still
- trouble breathing
- unsteadiness, trembling, or other problems with muscle control or coordination
- unusual bleeding or bruising
- unusual tiredness or weakness
- vaginal bleeding
- vision changes
- yellow eyes or skin
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
- Change in consciousness
- 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:
Rare
- Increased in sexual ability, desire, drive, or performance
- increased interest in sexual intercourse
Incidence not known
- Cramps
- dizziness
- drowsiness
- heartburn
- hiccups
- increased hair growth, especially on the face
- loss of appetite
- nausea or vomiting
- nearsightedness
- pain or discomfort in the chest, upper stomach, or throat
- redness of the skin
- unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
- 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.
Commonly used brand name(s)
In the U.S.
- Zarontin
Available Dosage Forms:
- Syrup
- Capsule, Liquid Filled
Therapeutic Class: Anticonvulsant
Chemical Class: Succinimide
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