Hesperian Health Guides

Medicines to Prevent Seizures

There are no medicines that ‘cure’ epilepsy. However, there are medicines that can prevent the seizures of most children—as long as they keep taking the medicine regularly. As long as a child has epilepsy—which may be for years or all his life—he must continue to take anti-seizure medicines.

Sometimes preventing seizures for a long time seems to help stop epilepsy permanently. For this reason, if the child has had many seizures in the past, it is usually wise for him to keep taking anti-seizure medicines regularly for at least one year after the last seizure. Only then should you gradually lower and stop the medication to see if he still needs it.

CAUTION! Great care is needed to select the medicines that help the individual child most, and which do her the least harm. Try to avoid giving so much medicine that she always seems sleepy, dizzy, slow-moving, or loses interest in things. A few seizures may be better than too much medicine—which can poison the child.

Choosing medicines

The best medicine (or medicines) for a child with epilepsy is one that is:

  • effective (prevents the seizures).
  • safe (has few side effects).
  • cheap (because it must be taken for years).
  • easy to take (long-acting, few doses a day).
  • easy to get.
WARNING! When child is having a seizure do not put his feet into a fire, it will not ‘frighten him back to life’ but will severely burn him.
A women putting a child's feet into the fire

Many different medicines are used for epilepsy. Some types of seizures are controlled better by one medicine and some by another medicine, or by a combination of medicines. Some children’s seizures are easy to control. Others are very difficult. It may be necessary to try different medicines and combinations to find the most effective treatment. In a few children, no medicines will control the seizures completely.

The best medicine to try first for almost all types of seizures is usually phenobarbital. Often it is very effective, and is relatively safe, cheap, and easy to take. Usually it is taken 2 times a day, but with some people only once a day at bedtime is enough.

The next best medicine for ‘big’ seizures is usually phenytoin. It is also fairly safe, cheap, and usually needs to be taken only once each night. (For some kinds of epilepsy, however, phenytoin may make seizures worse.)

For most epilepsies, phenobarbital and phenytoin are often the best drugs. First try each alone, and if that does not work, try both together. Most other drugs are less likely to be effective, are often less safe, and are much more expensive.

Unfortunately, many doctors prescribe more expensive, less safe, and often less effective medicines before trying phenobarbital or phenytoin. Partly this is due to drug companies that falsely advertise their more expensive products. In some countries, phenobarbital is difficult to get—especially in pill form. The result is that many children’s seizures are poorly controlled, using drugs that cause severe side effects and that are very costly. Rehabilitation workers need to realize this and do what they can to help provide the safest, cheapest medicines that will effectively control each child’s seizures.

CAUTION! To prevent choking, do not give medicines to a child while she is lying on her back, or if her head is pressed back. Always make sure her head is lifted forward. Never give medicines by mouth to a child while she is having a seizure, or while she is asleep or unconscious.

It is usually best to start with only one anti-seizure medicine—usually phenobarbital, if available. Start with a low to medium dose, and after a week, if seizures are not controlled and if there are no serious side effects, increase to a higher dose. After a few days, if the seizures are still not controlled, add a second medication—usually phenytoin, for ‘big seizures’. Again, start with a low to medium dose and gradually increase as needed.

CAUTION! When you stop or change a child’s medicine, do so gradually. Sudden stopping or changing the medicine may make seizures worse. Also, it may take several days for a new medicine to have its full effect.
A skull with cross bones

WARNING! All anti-seizure medicines are poisonous if a child takes too much. Be careful to give the right dose and to keep medicines out of reach of children.

Phenobarbital (phenobarbitione, Luminal)
For all types of seizures. Usually comes in:
tablets of 15 mg tablets of 30 mg (It costs less to buy 100 mg tablets and cut them into pieces.)
tablets of 60 mg tablets of 100 mg
Dosage: Because tablet sizes differ, we give the dosage in milligrams (mg).
The usual dose is 3 to 8 mg for each kg of body weight every day (3 to 8 mg/kg/day)— usually given in 2 doses (morning and evening):

Give 2 doses a day. In each dose give:
children over 12 50 to 150 mg
children 7 to 12 years 25 to 50 mg
children under 7 years 10 to 25 mg
Some children do better with 1 dose a day instead of 2 doses. Give twice the amount listed here at bedtime. But if the seizures return or the child has problems going to sleep or waking up, go back to 2 doses a day of the regular amount.
  • Too much can cause sleepiness or slow breathing.
  • Some very active children become over-active or behave badly.
  • Rare side effects include mild dizziness, eye-jerking, and skin rash.
  • Bone growth problems may occur—especially in children with mental slowness. Extra vitamin D may help.
  • Bitter taste. It may help to grind up the tablet and give it with honey or jam.
  • Habit forming.
CAUTION! If tablets of 100 mg are used, be very sure the family understands that they must be cut into pieces. Show them first and then have them do it.
A whole tablet and a tablet broken into four pieces
Giving a whole tablet instead of a small piece can poison the child.
skull and cross bones
Phenytoin (diphenylhydantoin, Dilantin)
For many types of seizures except brief seizures that suddenly throw the child out of balance (‘jolt seizures’) or ‘minor seizures’ with staring, blinking, or fast movement of eyes. (Phenytoin may make these kinds of seizures worse.)
Usually comes in: capsules or tablets of 25 mg, 50 mg,and 100 mg syrup with 30 mg in each 5 ml (1 teaspoon)
Dosage: Give 5 to 10 mg/kg/day in 2 divided doses, but do not exceed 300 mg/day.
Start with the following dose once a day:
children over 12 years 100 to 300 mg
children 7 to 12 years 100 mg
children 6 or under 50 mg
After 2 weeks, if the seizures are not completely prevented, the dose can be increased little by little, but not to more than twice the amount. The difference between not enough and too much can be very small. If child has no seizures during several weeks, try lowering the dose little by little until you find the lowest dose that prevent the seizures.

WARNING! Watch for dizziness, eye-jerking, seeing double, and severe sleepiness. Lower the dose if any of these occur. They are early signs of poisoning, which could cause permanent brain damage.

  • Swelling and abnormal growth of the gums often occurs with long-time use. It can be partly prevented by good mouth care. Be sure the child brushes or cleans his teeth and gums well after eating. If he cannot do it by himself, help him, or better, teach him. If the gum problem is severe, consider changing medicines. (See Where There Is No Dentist)
  • Occasional side effects: increased body hair, rash, loss of appetite, vomiting.
  • High dosage may cause liver damage.
  • Bone growth problems sometimes occur—especially in children who are mentally slow. Extra vitamin D may help.
very swollen, sore gums almost covering teeth—caused by not keeping teeth clean while taking phenytoin
swollen upper gums

WARNING! Sudden stopping of phenytoin may cause the child to have a long-lasting seizure. Therefore, when stopping or changing the medicine, lower the dosage gradually.

Carbamazepine (Tegretol)
Useful for almost all types of seizures as a second choice, or in combination. Especially useful for ’psychomotor’ seizures. High cost is a disadvantage. (Unfortunately, many doctors prescribe it as first choice when cheaper drugs such as phenobarbital are likely to work as well or better.)

Usually comes in: tablets of 100 mg or 200 mg

Dosage: 10 to 25 mg/kg/day divided into 2 to 4 doses. Or you can start with these doses 4 times a day:
children 10 to 15 years 200 mg
children 5 to 10 years 150 mg
children 1 to 5 years 100 mg
children under 1 year old 50 mg
It is best to take it with meals. The dose of carbamazepine should be adjusted to the individual. Depending on how well it controls the seizures, it can be raised to 30 mg/kg/day (but no higher) or dropped to 10 mg/kg/day. Try to give the lowest amount of medicine that stops the seizures.
  • Rarely causes liver damage or reduces ability of blood to clot, or severe skin problems. If a rash develops, stop using it.


  • Primidone (Mysoline) For all seizures. Start with low doses and gradually increase to 10 to 25 mg/kg/day in 2 to 4 divided doses. May cause sleepiness, dizziness, vomiting, or rash.
  • Ethosuximide (Zarontin) First choice for ‘absence seizures’ with blank staring, eye-fluttering, and perhaps strange motions—especially if the seizures occur in groups in the morning and evening. Give 10 to 25 mg/kg/day in 1 or 2 doses, with food to avoid stomach ache. Rarely causes liver damage.
  • Valproate (Depakene) Used alone or in combination with other anti-seizure drugs, except carbamazepine, for ‘minor seizures’ with blank staring or ‘absences,’ especially when the seizures occur in groups. For children between 1 and 12 years. The dosage for a child who weighs up to 20 kg is initially 20 mg/kg/day in 2 to 3 divided doses. (For example, a child weighing 10 kg would take 200 mg a day, and a child weighing 20 kg would take 400 mg a day.) Children over 20 kg can start with 400 mg a day in divided doses, and the dose can be increased until the seizures are controlled (usually up to 30 mg/kg/day). Never give more than 60 mg/kg/day. Few side effects. May cause liver damage, especially for children younger than 2 years old, so do not use for small children, women, or girls who could get pregnant.
  • Corticosteroids (or corticotropin) These are sometimes tried for ‘baby spasms’ and ‘jolt seizures’ that are not controlled by other medicines. Long-term use of these medicines causes serious and possibly dangerous side effects. They should be used only with highly skilled medical advice when all other possible medicines have failed.
  • Diazepam (Valium) Sometimes used for ‘newborn seizures’ or ‘baby spasms’, but other medicines should be tried first. May cause sleepiness or dizziness. Mildly habit forming. Give about 0.2 mg/kg/day in divided doses.
CAUTION! DURING PREGNANCY: Many of the anti-seizure drugs, especially especially phenytoin and valproate, may increase the risk of birth defects when taken by pregnant women. Also, some of the drug goes into breast milk. Therefore, pregnant women should use these drugs only when seizures are common or severe without them. Women taking seizure medicine should not breast feed if they are able to feed their babies well without breast milk. Phenobarbital is probably the safest anti-seizure medicine during pregnancy.


When a seizure has lasted more than 15 minutes:

  • if someone knows how, inject IV diazepam (Valium) or phenobarbital into the vein.
CAUTION! Diazepam and phenobarbital must both be injected very slowly. For diazepam, take at least 3 minutes to inject the dose for children. For phenobarbital, inject children at the rate of 30 mg/ minute or slower, and in adults, not more than 100 mg/minute.
Diazepam bottle
Doses for injectable diazepam:
Adults 5 to 10 mg
Children 7-12 years 3 to 5 mg
Children under 7 1 mg for every 5 kg of body weight

Phenobarbital bottle
Doses for injectable phenobarbital:
Adults 200 mg
Children 7-12 years 150 mg
Children 2-6 years 100 mg
Children under 2 years 50 mg
  • or put a ‘suppository’ of diazepam, paraldehyde, or phenobarbital up the rectum.
A child being injected through the anus while being held
Putting diazepam up the rectum (without a needle!) works faster than injecting it into a muscle.

Note: These medicines do not work as fast or well when they are injected into a muscle. If you only have injectable or liquid medicine, put it up the rectum with a plastic syringe without a needle. Or grind up a pill of diazepam or phenobarbital, mix with water, and put it up the rectum.

If the seizure does not stop in 15 minutes after giving the medicine, repeat the dose. Do not repeat more than once.

This page was updated:21 Nov 2019