Primidone Benzodiazepines

Valproic acid causes hair loss in about 5% of patients, but this effect is reversible. Transient gastrointestinal effects are common, and some mild behavioral effects have been reported. Metabolic effects, including hyperglycemia, hyperglycinuria, and hyperammonemia, have been reported. An increase in body weight also has been noted. Valproic acid is not a CNS depressant, but its administration may lead to increased depression if it is used in combination with phenobarbital, primidone, benzodiazepines, or other CNS depressant agents. 

From the chemical point of view, formally, antiepileptic drugs could be classified as derivatives of hydantoins (phenytoin, mephenytoin, ethotoin), barbiturates (phenobarbital, mephobarbital, and primidone), succinimides (ethosuximide, methosuximide, phensux-imide), benzodiazepines (diazepam, chlorodiazepoxide, clonazepam, lorazepam), oxazo-lidines (trimethadione, paramethadione), and also valproic acid, carbamazepine, and acetazolamide. 

Drugs acting on GABA/glutamate - hypnotics/anxiolytics barbiturates, benzodiazepines, chlormethiazole, chloral derivatives, baclofen - anticonvulsants phenobarbitone, primidone, phe-nytoin, sodium, valproate, carbamazepine - alcohol, phencyclidine, ketamine... 

Type II Multiple actions enhance GABAergic inhibition, reduce T-calcium currents, and possibly block SRF Valproic acid Benzodiazepines Phenobarbital Primidone... 

Clinically important, potentially hazardous interactions with alcohol, anticholinergics, barbiturates, benzodiazepines, butabarbital, chloral hydrate, chlordiazepoxide, chlorpromazine, clonazepam, clorazepate, diazepam, ethchlorvynol, fluphenazine, flurazepam, hypnotics, lorazepam, MAO inhibitors, mephobarbital, mesoridazine, midazolam, narcotics, oxazepam, pentobarbital, phenobarbital, phenothiazines, phenylbutazone, primidone, prochlorperazine, promethazine, quazepam, secobarbital, sedatives, temazepam, thioridazine, tranquilizers, trifluoperazine, zolpidem... 

Clinically important, potentially hazardous interactions with amlodipine, anisindione, anticoagulants, aprepitant, atorvastatin, barbiturates, benzodiazepines, butabarbital, carbamazepine, chlordiazepoxide, clarithromycin, clonazepam, dorazepate, corticosteroids, cyclosporine, dexamethasone, diazepam, dicumarol, erythromycin, ethotoin, felodipine, flurazepam, fluvastatin, fosphenytoin, isradipine, itraconazole, ketoconazole, lorazepam, lovastatin, mephenytoin, mephobarbital, midazolam, nicardipine, nifedipine, nimodipine, nisoldipine, oxazepam, pentobarbital, phenobarbital, pimozide, pravastatin, primidone, quazepam, rifampin, secobarbital, simvastatin, St John s wort, temazepam, warfarin... 

Primary, commonly used antiepileptics include phenytoin, phenobarbital, primidone, carbamazepine, ethosuximide and valproic acid. In addition, two benzodiazepines, diazepam and... 

The use of benzodiazepines with antiepileptics is common and possibly accompanied by some changes in serum levels, which are normally of limited clinical importance. However, isolated interactions have been reported between chlordiazepoxide or cloba-zam and phenobarbital between clonazepam and lamotrigine or primidone and between clorazepate and primidone. 

None of the interactions between the benzodiazepines and antiepileptics described here appear to be of major clinical importance, with the possible exception of the interaction between clobazam and felbamate. If both drugs are given be aware that additive sedative or other adverse effects may occur. This may also be possible in some rare cases with chlordiazepoxide or clobazam and phenobarbital clonazepam and lamotrigine or primidone and clorazepate and primidone. 

The useful antiepileptic agents belong to several chemical classes. Most of the drugs introduced before 1965 are closely related in structure to phenobarbital, the oldest member of this therapeutic class. These include the hydantoins, phenytoin, mephenytoin, and ethotoin the deoxybarbiturate, primidone the oxazolidine-diones, trimethadione, and paramethadione and the succinimides, ethosuximide, methsuximide, and phensuximide. The agents introduced after 1965 include the benzodiazepines clonazepan and clorazepate, an iminostilbene, carbamazepine, and a branched-chain carboxylic acid, valproic acid. 

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