DRUG TREATMENT FOR EPILEPSY

by National Society for Epilepsy

Identification of the type of epilepsy is important for correct treatment. People with newly diagnosed epilepsy should be treated with one drug at a time. The effectiveness of drug treatment should be closely monitored, and the drug dose altered as appropriate, in order to achieve complete control of seizures.

If complete control of seizures cannot be achieved, despite appropriate and accurate treatment, the drug regime should be kept as simple as possible (rational therapy). This minimises side-effects, reduces chronic toxicity, and encourages compliance.

Compliance

It is essential for drugs to be taken reliably, as prescribed. The exact timing of doses is not crucial, but it is wise to take the correct doses at approximately correct time intervals. This is especially important for controlled released tablets such as Tegretol Retard. One missed dose on a rare occasion is unlikely to be dangerous and result in seizures. Drug wallets can help with compliance.

Side-effects

All drugs can have side-effects. Since anti-epileptic drugs act on the brain, drowsiness, sedation, nausea, and unsteadiness may occur. Sometimes this occurs when the drug is taken for the first time, and normally wears off. These effects may also be experienced if the dose is too high. Persistent unwelcome effects should be brought to the attention of a doctor. If drugs are taken over a long period, chronic side-effects may be experienced. These are not inevitable, and the risk will be minimised by rational therapy. No one should stop taking anti-epileptic drugs abruptly without seeking medical advice.

Dosage

The figures given below are average daily dose ranges for adults. Treatment may commence with smaller doses, and the most appropriate dose for any individual may be found, during careful monitoring, to be higher than the average.

First line drugs
Carbamazepine

Available as:

• Carbamazepine tablets BP (100 mg, 200 mg, 400 mg)
• Tegretol tablets (100 mg, 200 mg, 400 mg)
• Chewtabs (100 mg)
• Tegretol Retards tablets (200 mg, 400 mg)

Average total daily adult dose

600 mg to 1,600 mg, divided up into four doses in one day.

Treatment

Effective against generalised tonic-clonic and partial seizures. Ineffective against absences.

Possible side-effects

Skin rash, double vision, unsteadiness, and nausea may occur initially, or if the dose is too high. Ethosuximide Available as:

• Zarontin capsules (250 mg)
• Emeside capsules (250 mg)
• Emeside syrup (250 mg/5 ml)

Average total daily adult dose

1,000 mg to 1,500 mg, divided up into two or three doses in one day.

Treatment

Effective against absences only.

Possible side-effects

Nausea and drowsiness may occur.

Lamotrigine

Available as:

• Lamactal tablets (25 mg, 50 mg, 100 mg)

Average total daily adult dose

200 mg to 400 mg, or (if also taking sodium valproate) 100mg to 200 mg, divided up into two doses in one day.

Treatment

Recommended in partial and generalised tonic-clonic seizures, where previous treatment has been ineffective.

Possible side-effects

Skin rash, drowsiness, double vision, dizziness, and headache may occur.

Phenytoin

Available as:

• Phenytoin tablets BP (50 mg, 100 mg)
• Epanutin capsules (25 mg, 50 mg, 100 mg)
• Epanutin chewable Infatabs (50 mg)
• Epanutin suspension (30 mg/5 ml)

Average total daily adult dose

200 mg to 500 mg, divided up into one or two doses in one day.

Treatment

Effective against generalised tonic-clonic and partial seizures. Ineffective against absences. Serum level monitoring essential, because the relationship between dose and serum level is complex.

Possible side-effects

Skin rash, drowsiness, unsteadiness, and slurred speech may occur if the dose is too high. Coarsening of facial features, overgrowth of gums, and acne, may be a problem with prolonged therapy.

Sodium Valproate

Available as:

• Epilim tablets (100 mg, 200 mg, 500 mg)
• Epilim chewable tablets (100 mg)
• Epilim sugar-free liquid (200 mg/ 5ml)
• Epilim syrup (200 mg/5 ml)
• Epilim chrono tablets (200 mg, 300 mg, 500 mg)

Average total daily adult dose

500 mg to 2,000 mg, divided up into one or two doses in one day.

Treatment

Effective against generalised tonic-clonic and partial seizures, and absences.

Possible side-effects

Drowsiness and tremor are infrequent side-effects. Hair loss occurs in some people, but this is usually not catastrophic, and is usually reversible if the dose is reduced. Liver damage due to sodium valproate is very uncommon.

Second line drugs
Acetazolamide

Available as:

• Diamox tablets (250 mg, 500 mg)

Average total daily adult dose

250 mg to 1,000 mg, divided up into two or three doses in one day.

Treatment

Effective against generalised tonic-clonic and partial seizures, and atypical absences.

Possible side-effects

Lack of appetite, loss of weight, drowsiness, depression, pins and needles in hands and feet, joint pains, increased urine output, thirst, headache, dizziness, fatigue, irritability, may all occur.

Clobazam

Available as:

• Frisium capsules (10 mg); doctors can only prescribe these on the NHS as Clobazam SLS

Average total daily adult dose

10 mg to 30 mg, divided up into one or two doses in one day.

Treatment

Effective against generalised tonic-clonic and partial seizures, but tolerance frequently develops.

Possible side-effects

Drowsiness may occur, but this drug is much less sedating than clonazepam or diazepam.

Clonazepam

Available as:

• Rivotril tablets (0.5 mg, 2 mg)

Average total daily adult dose

1 mg to 3 mg, divided up into two doses in one day.

Treatment

Effective against partial seizures, absences, and myoclonic jerks.

Possible side-effects

Drowsiness and sedation are quite common, but these may wear off, and tolerance tends to develop.

Gabapentin

Available as:

• Neurontin tablets (300 mg, 400 mg)

Average total daily adult dose

900 mg to 2,400 mg, divided up into three doses in one day.

Treatment

Recommended in partial seizures, where previous treatment has been ineffective.

Possible side-effects

Drowsiness, dizziness, headache, and fatigue may occur.

Phenobarbitone

Available as:

• Phenobarbitone tablets BP (15 mg, 30 mg, 60 mg)

Average total daily adult dose

60 mg to 180 mg, divided up into one or two doses in one day.

Treatment

Effective against generalised tonic-clonic and partial seizures.

Possible side-effects

Drowsiness may occur initially, and sedation and slowing of mental performance may persist.

Piracetam

Available as:

• Nootropil capsules (400 mg)
• Nootropil tablets (800 mg, 1,200 mg)
• Nootropil oral solution (1,200 mg); to be taken with water, because it has a bitter after taste

Average total daily adult dose

20 g, divided up into up to three doses in one day.

Treatment

Recommended in myoclonic seizures, where previous treatment has been ineffective.

Possible side-effects

Very rare, but may include weight gain, diarrhoea, insomnia, drowsiness, nervousness, depression, and rash.

Primidone

Available as:

• Mysoline tablets (250 mg)
• Mysoline oral suspension (250 mg/ 5 ml)

Average total daily adult dose

500 mg to 1,000 mg, divided up into two doses in one day.

Treatment

Primidone is partially metabolised to phenobarbitone in the body. Effective against generalised tonic-clonic and partial seizures.

Possible side-effects

Nausea, unsteadiness, and drowsiness may occur initially, but sedation and slowing of mental performance may persist.

Vigabatrin

Available as:

• Sabril tablets (500 mg)
• Sabril sachets (500 mg)

Average total daily adult dose

1,000 mg to 4,000 mg, divided up into two doses in one day.

Treatment

Recommended in partial and secondary generalised seizures, where previous treatment has been ineffective.

Possible side-effects

Drowsiness, nausea, behaviour and mood changes may occur. Psychotic reactions have been reported.