Phenytoin Clobazam

Clobazam Phenytoin Primidone Interaction inconsistent, usually of no clinical significance Unknown... 

Carbam- azepine Valproic acid, Phenytoin, Clobazam Primidone, Pheno barbital... 

For simple and complex partial seizures and secondary generalized tonic-clonic seizures, the first line drugs are - carbamazepine, valproate and phenytoin. Second line drugs include - acetazolamide, clobazam, clonazepam, ethosuximide, felbamate, gabapentin, lamotrigine, levetiracetam, oxacarbamazepine, primidone, tiagabine, topiramate and vigabactin. 

For atypical absence, tonic and clonic seizures, first line treatment is with valproate and second line with acetazolamide, carbamazepine, clobazam, clonazepam, ethosuximide, felbamate, lamotrigine, oxacarbamazepine, phenobarbitone, phenytoin, primidone or topiramate. 

Several metabolic interactions between clobazam and other antiepileptic drugs have been reported, in particular phenytoin intoxication after the addition of clobazam (SED-12, 98). 

Canadian Study Group for Childhood Epilepsy. Clobazam has equivalent efficacy to carbamazepine and phenytoin as monotherapy for childhood epilepsy. Epilepsia 1998 39(9) 952-9. 

Valproate, clonazepam, or clobazam may be safer alternatives in patients who have had a rash from aromatic anticonvulsants. However, in a 41-year-old man a fixed drug eruption that occurred after phenytoin and carbamazepine also occurred after valproate (SEDA-22, 83). 

Phenobarbital Phenytoin Primidone Felbamate Lamotrigine Tiagabide Topiramate Valproate Zonisamide Clobazam Clonazepam Diazepam usually compensated by the effect of the added drug risk of toxicity when interfering drug is discontinued drug... 

Clobazam Carbamazepine Primidone Valproate Phenytoin Interaction inconsistent, usually of little clinical significance Inhibition of metabolism of the object drug... 

Cimetidine Carbamazepine Clobazam Clonazepam Diazepam Phenytoin Valproate Risk of toxicity, particularly with phenytoin Inhibition of metabolism of the object drugs... 

Ethanol Clobazam Diazepam Phenytoin Risk of toxicity of the object drugs chronic ethanol can reduce serum phenytoin concentrations Inhibition of metabolism induction of phenytoin metabolism by chronic ethanol... 

Noninterfering clobazam, clonazepam, diazepam, ethosuximide, phenytoin, valproic acid... 

A 65-year-old man taking phenytoin 200 mg daily and clobazam developed signs of phenytoin toxicity (vertigo, ataxia, somnolence) within a week of starting ticlopidine 250 mg daily. His serum phenytoin levels had risen from 18 mg/L to 34 mg/L. When the phenytoin dosage was reduced to 200 mg daily the toxic symptoms disappeared within a few days and his serum phenytoin levels fell to 18 mg/L. To test whether an interaction had occurred, the ticlopidine was stopped, whereupon the serum phenytoin levels fell, within about 3 weeks, to 8 mg/L, during which time the patient... 

The authors of one study suggest that antiepileptics with fewer enzyme-inducing properties than phenytoin should he used as prophylaxis if busulfan is given for bone marrow transplant pretreatment. One UK manufacturer recommends prophylaxis with a benzodiazepine rather than phenytoin if high-dose busulfan is given. Clobazam , (p.619), has been suggested as a possible alternative to phenytoin. ... 

Further reports attribute inereased phenytoin serum levels and phenytoin toxieity to chlordiazepoxide, clobazam, clonazepam, " and diazepam. " ... 

A study in 5 patients given phenytoin 250 to 400 mg daily found that serum clonazepam levels were reduced by more than 50%, and another study found that phenytoin decreased the clearance of clonazepam by about 50%. In a further study phenytoin reduced the plasma levels of clobazam and increased the levels of norclobazam (the principal metabolite). Diazepam and oxazepam may be similarly affected in epileptic patients given phenytoin. 

Zifkin B, Sherwin A, Andermann F, Phenytoin toxicity due to interaction with clobazam. Neumlogy (1991) 41, 313-14. 

Drag-drag interactions Care must be taken in using stiripentol as add-on therapy with carbamazepine, clobazam, pheno-barbital, phenytoin, and valproate, because stiripentol inhibits the metabolism of these drugs and/or their metabolites [286 ]. 

A 60-year-old male with known cerebral palsy and epilepsy on phenytoin and clobazam, presented to emergency department with a community-acquired pneumonia which was treated with levofloxacin. Phenytoin levels on admission were high and therefore phenytoin was omitted until levels were in the therapeutic range. Ten days into admission, he developed status epilepticus that necessitated intubation and ventilation for airway protection. Continuous EEC monitoring showed nonconvulsive status epilepticus. 

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