Partial seizures drugs used

Felbamate, proprietary name Felhatol, was approved for primary or adjunctive therapy of partial seizures. Its use is limited to those patients who fail other drug treatments, because felbamate carries with it a substantial risk of aplastic anemia and hver failure that is not related to the blood level. Biweekly monitoring of complete blood count, serum ammotransferases, and bilirubin is recommended to detect early onset of these side effects. Felbamate is particularly effective in control of Lennox-Gastaut syndrome. 

Place in Therapy. Phenytoin has long been a first-fine AED for primary generalized convulsive and partial seizures. Its use in therapy may be reevaluated as more experience is gained with newer AEDs. Phenytoin or fosphenytoin is a first-line drug for the treatment of status epUepticus. 

It is indicated for use as monotherapy or adjunctive therapy for partial seizures in adults and as monotherapy and adjunctive therapy for partial seizures in patients as young as 4 years of age. It is also a potential first-line drug for patients with primary, generalized convulsive seizures. 

Phenobarbital is still used for the management of partial seizures, generalized tonic-clonic seizures and for the control of status epilepticus. However because of its low therapeutic index and the possibility of dependence, phenobarbital has largely been displaced by other anticonvulsants. For newborns phenobarbital is often the drug of first choice. If given together with sodium valproate the metabolism of phenobarbital may be inhibited while in combination with carbamazepine the serum concentrations of carbamazepine will be reduced due to enzyme induction by phenobarbital. 

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. 

Oxcarbazepine is a derivative of carbamazepine and although its precise mechanism of action is unknown it has similar properties as carbamazepine and is also used for the treatment of primary generalized tonic-clonic seizures and partial seizures. Also the adverse effects are similar to those of carbamazepine. However the drug interaction profile is different as oxcarbazepine has hardly any enzyme-inducing capacity. 

Valproic acid has become a major AED against several seizure types. It is highly effective against absence seizures and myoclonic seizures. In addition, valproic acid can be used either alone or in combination with other drugs for the treatment of generalized tonic-clonic epilepsy and for partial seizures with complex symptoms. 

Gabapentin is recommended as adjunctive therapy in the treatment of partial seizures in adults. When used with other drugs, it appears to be an effective AED it is usually not effective when employed alone for patients with severe seizures. 

Benzodiazepines and barbiturates are used as anticonvulsant drugs in the treatment of epilepsy. Epilepsy, a medical disorder characterized by recurrent seizures, has many different forms. The four most common seizure types are generalized tonic-clonic seizures (old name grand mal seizures), generalized absence seizures (petit mal seizures), complex partial seizures (psychomotor or temporal lobe seizures), and simple partial seizures (focal seizures). 

Chapters 16, 62) topiramate, a drug used for partial and generalized tonic-clonic seizures (see Chapter 24) and baclofen, a GABAB receptor antagonist used as a spasmolytic (see Chapter 27). Based on evidence from model systems,... 

Drugs Used in Partial Seizures Generalized Tonic-Clonic Seizures... 

Phenobarbital is useful in the treatment of partial seizures and generalized tonic-clonic seizures, although the drug is often tried for virtually every seizure type, especially when attacks are difficult to control. There is little evidence for its effectiveness in generalized seizures such as absence, atonic attacks, and infantile spasms it may worsen certain patients with these seizure types. 

Phensuximide and methsuximide are phenylsuccinimides that were developed and marketed before ethosuximide. They are used primarily as antiabsence 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 drugs used for generalized tonic-clonic seizures are the same as for partial seizures in addition, valproate is clearly useful. 

Levetiracetam (Keppra). Levetiracetam has been successful in treating partial seizures in adults when used in conjunction with traditional antiseizure drugs. This drug does not appear to decrease seizure activity via one of the common antiseizure mechanisms (stabilize sodium channels, increase GABA inhibition, and so forth), and the mechanism of this drug is therefore unknown. Levetiracetam is usually well tolerated, although some patients may experience sedation, dizziness, and generalized weakness. 

Topiramate (Topamax). Topiramate is used primarily as an adjunct to other medications in adults with partial seizures. This drug appears to limit seizure activity through several complimentary mechanisms including inhibition of sodium channel opening, blockade of excitatory amino acid receptors, and stimulation of GABA receptors.2,41 Primary side effects include sedation, dizziness, fatigue, and ataxia. 

Vigabatrin is used as an adjunctive antiepileptic in patients with resistant partial epilepsy with or without secondary generalization, unresponsive to other therapy [2]. Nowadays, vigabatrin is rarely used in the treatment of partial seizures due to several irreversible visual field constrictions associated with its chronic use [57-62], It is regarded by many authorities as a drug of choice in infants with west syndrome (infantile spasms), particularly in cases associated with tuberous sclerosis [62],... 

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