If you have a certain kind of seizure condition, your doctor might suggest Sabril as a treatment option. It’s a prescription drug used to treat the following conditions:

The active ingredient in Sabril is vigabatrin. (An active ingredient is what makes a drug work.)

Sabril is part of a group of drugs called anti-seizure drugs (also called antiepileptic drugs). Sabril is taken by mouth. It comes as a tablet and powder that you mix with water to form a solution.

This article describes the dosage and administration of Sabril. To learn more about Sabril, see this in-depth article.

Note: This article covers Sabril’s usual dosages, which are provided by the drugmaker. But when taking Sabril, always follow the dosage that your doctor prescribes.

* “Refractory” means the condition hasn’t improved with other past treatments.

Below is information about Sabril’s dosage and timing.

Note: This chart highlights the basics of Sabril’s dosage and frequency. Be sure to read on for more detail.

Sabril’s formsSabril’s strengthStarting dosage for adults
• tablet
• powder that’s mixed with water
500 milligrams (mg)500 mg taken by mouth twice daily

What are the forms of Sabril?

Sabril comes as tablets and as packets of powder that are mixed with water to form a solution.

What strength does Sabril come in?

Sabril comes in one strength: 500 mg.

What are the usual dosages of Sabril?

Your doctor will likely start you on a low dosage and adjust it over time to reach the right amount for you. They’ll ultimately prescribe the smallest dosage that provides the desired effect.

The information below describes dosages that are commonly used or recommended. But be sure to take the dosage your doctor prescribes for you. They’ll determine the best dosage to fit your needs.

If you want to stop taking Sabril, be sure to talk with your doctor first. They’ll have you slowly decrease your dose over a period of time. If you stop your treatment suddenly, there’s a risk of status epilepticus. (With this condition, you have seizures that don’t stop until you get emergency medical care.) Decreasing your dose slowly helps lower your risk of status epilepticus.

Dosage for refractory complex partial seizures in adults

For refractory* complex partial seizures (also called focal onset seizures), the starting dosage of Sabril in adults is typically 500 mg taken twice per day. Your doctor may then increase your dose slowly. This is usually done by adding 500 mg to your daily dose each week until you reach a long-term dosage of 1,500 mg taken twice per day.

* “Refractory” means the condition hasn’t improved with other past treatments.

What’s the dosage of Sabril for children?

When prescribed for children, Sabril’s dosage is determined by weight.

Below are general guidelines based on information from the drugmaker. Be sure to follow the dosage instructions from your child’s doctor.

If your child needs to stop taking Sabril, be sure to talk with their doctor first. They’ll have you slowly decrease your child’s dose over a period of time. If you stop their treatment suddenly, your child has a risk of status epilepticus. (With this condition, you have seizures that don’t stop until you get emergency medical care.) Decreasing your child’s dose slowly helps lower their risk of status epilepticus.

Dosage for infantile spasms

Your infant’s dose will be based on their weight in kilograms (kg). (One kg equals about 2.2 pounds [lb].) Your child’s doctor will calculate their dosage and will explain how to mix the Sabril powder packets with water.

The typical Sabril starting dose is 50 mg/kg per day, divided into two doses. For example, if your infant weighs 5 kg, which is about 11 lb, their starting dose will be 250 mg per day. You’ll split that in two doses, so you’ll give your child a 125-mg dose twice per day.

If your child’s doctor increases their dose, the daily dose is typically increased by 25 mg/kg to 50 mg/kg every 3 days. The maximum recommended dosage for this use is 150 mg/kg per day.

Dosage for refractory* complex partial seizures in children

Your child’s Sabril dose will be based on their body weight in kg. The table below has details about the starting dose and long-term dose based on your child’s weight. If your child weighs more than 60 kg, they’ll likely follow the adult dosing recommendations. (To learn about the Sabril dosage used in adults, see “What are the usual dosages of Sabril?” above.)

Child’s weightStarting dosageLong-term dosage
10 kg to 15 kg (about 22 lb to 33 lb)175 mg taken twice per day525 mg taken twice per day
15 kg to 20 kg (about 33 lb to 44 lb)225 mg taken twice per day650 mg taken twice per day
20 kg to 25 kg (about 44 lb to 55 lb)250 mg taken twice per day750 mg taken twice per day
25 kg to 60 kg (about 55 lb to 132 lb)250 mg taken twice per day1,000 mg taken twice per day

If your child’s doctor increases their daily dose, it will be based on how their body responds to the drug. Dosage increases are typically done once per week.

If after 3 months of treatment, Sabril isn’t working to treat your child’s seizures, their doctor may have them switch to a different medication.

* “Refractory” means the condition hasn’t improved with other past treatments.

Is Sabril used long term?

Yes, Sabril is usually used as a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely take it long term.

Dosage adjustments

Your doctor may start you on a lower dose if you have kidney problems, such as chronic kidney disease.

You’ll likely have vision tests done before and during your Sabril treatment. If you have vision changes while taking Sabril, your doctor may have you switch to a different medication.

The dosage of Sabril you’re prescribed may depend on several factors. These include:

  • the type and severity of the condition you’re using the drug to treat
  • your age
  • weight when given to children
  • the form of Sabril you’re using
  • other conditions you may have (see “Dosage adjustments” just above)

Below are answers to some commonly asked questions about Sabril’s dosage.

Is Sabril used to treat anxiety? If so, what’s the dosage?

No, Sabril isn’t used to treat anxiety.

Some medications that treat seizures are also prescribed off-label in smaller doses to treat anxiety, but Sabril is not one of them. (Off-label drug use is when an FDA-approved drug is prescribed for a purpose other than what it’s approved for.)

For example, gabapentin belongs to the same group of drugs as Sabril and is sometimes prescribed off-label for anxiety.

If you’re looking at treatment options for anxiety, talk with your doctor. They’ll help you find a treatment that works for you.

Is there a Sabril dosage that’s recommended for someone who is breastfeeding?

No, there isn’t a recommended dosage of Sabril for someone who’s breastfeeding.

Sabril is not recommended while breastfeeding because of the risks to the breastfed child. If you’re currently breastfeeding or planning to breastfeed, talk with your doctor about your treatment options.

You’ll take Sabril by mouth. It comes as a tablet or powder that you mix with water to form a liquid solution. The strength of this liquid solution is 50 milligrams per milliliter (mg/mL). Your doctor will calculate the dosage and tell you how much to take for the correct dose. Be sure to use an oral syringe from a pharmacy. (A household spoon isn’t accurate for measuring liquid medications.)

To learn how to mix the Sabril powder into a liquid solution, see these step-by-step instructions. If you still have questions on how to make the solution, talk with your doctor or pharmacist.

For information on the expiration, storage, and safe disposal of Sabril, see this article.

Accessible drug containers and labels

If you find it hard to read the prescription label on your medication, tell your doctor or pharmacist. Some pharmacies provide medication labels that:

  • have large print or use braille
  • feature a code you can scan with a smartphone to change the text to audio

Your doctor or pharmacist may be able to recommend pharmacies that offer these accessibility features if your current pharmacy doesn’t.

If you have trouble opening medication bottles, let your pharmacist know. They may be able to supply Sabril tablets in an easy-open container. They may also have tips to help make it simpler to open the drug’s container.

It’s important that you do not miss any doses of Sabril. Before starting your Sabril treatment, talk with your doctor about what to do if you miss a dose. If your child takes Sabril, ask their doctor about what to do if they vomit or spit up a dose.

If you need help remembering to take your dose of Sabril on time, try using a medication reminder. This can include setting an alarm or downloading a reminder app on your phone.

Do not take more Sabril than your doctor prescribes, as this can lead to serious side effects.

Symptoms of overdose

Symptoms caused by an overdose can include:

What to do in case you take too much Sabril

Call your doctor right away if you think you’ve taken too much Sabril. You can also call 800-222-1222 to reach the American Association of Poison Control Centers or use its online resource. But if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.

The sections above describe the usual dosage provided by the drugmaker. If your doctor recommends Sabril for you, they’ll prescribe the dosage that’s right for you.

Remember, you should not change your dosage of Sabril without your doctor’s recommendation. Only take Sabril exactly as prescribed. Talk with your doctor if you have questions or concerns about your current dosage.

Here are some examples of questions you may want to ask your doctor:

  • If my other seizure medications change, should my Sabril dosage change?
  • If Sabril is working well for me, how long will I take it?
  • Will a lower dose of Sabril lower my risk of side effects?
  • How will my Sabril dose change if I have kidney problems?

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.