Partial seizures Anti seizure drugs

Largactil is a proprietary preparation of chlorpromazine, an aliphatic antipsychotic with marked sedation and moderate antimuscarinic and extrapyramidal side-effects. Serenace is a proprietary preparation of haloperidol, a butyrophenone antipsychotic with marked extrapyramidal side-effects, moderate sedation but not very likely to cause hypotension. Tegretol is a proprietary preparation of carbamazepine, an anti-epileptic drug indicated in partial and secondary generalised tonic-clonic seizures, primary generalised tonic-clonic seizures, trigeminal neuralgia and in the prophylaxis of bipolar disorder unresponsive to lithium. 

Primidone is an other second line barbiturate used orally to control tonic-clonic and partial seizures. It is a pro-drug as it is metabolized to phenobarbital and phenylethylmalonamide (PEMA), however both the parent compound as well as the metabolites have anti seizure activity. Its use is more difficult to monitor and adverse effects occur even more frequently than with phenobarbital. 

Some drugs are more easily withdrawn than others. In general, withdrawal of anti-absence drugs is easier than withdrawal of drugs needed for partial or generalized tonic-clonic seizures. Barbiturates and benzodiazepines are the most difficult to discontinue weeks or months may be required, with very gradual dosage decrements, to accomplish their complete outpatient removal. 

Phensuximide and methsuximide are phenylsuccinimides that were developed and marketed before ethosuximide. They are used primarily as anti-absence drugs. Methsuximide is generally considered more toxic, and phensuximide less effective, than ethosuximide. Unlike ethosuximide, these two compounds have some activity against maximal electroshock seizures, and methsuximide has been used for partial seizures by some investigators. The desmethyl metabolite of methsuximide has a half-life of 25 hours or more and exerts the major antiseizure effect. The toxicity and reduced effectiveness of phensuximide when compared with methsuximide has been investigated, and the failure of the desmethyl metabolite to accumulate in the former probably explains its relatively... 

Withdrawal Withdrawal from antiseizure drugs should be accomplished gradually to avoid increased seizure frequency and severity. In general, withdrawal from anti-absence drugs is more easily accomplished than withdrawal from drugs used in partial or generalized tonic-clonic seizure states. 

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