OTHER MEDICATIONS

Valproic Acid:    This medication is effective in humans with all types of seizures; however, it is metabolized very quickly in dogs and therefore its use is limited.  Valproic Acid is primarily used in combination with other drugs such as Phenobarbital.  Potential side effects include loss of hair and liver disease.

Diazepam (Valium), Clonazepan, Lorazepam and Clorazepate: These medications are all part of the benzodiazepines and are potent anti-seizure drugs, but they all have characteristics that limit their use for maintenance of seizures in dogs.  First, they are only effective for a short time requiring frequent administration to maintain adequate serum levels.  Second, long term use of this category of drug reduces its effectiveness in controlling seizures.  Long term use of any benzodiazepine may prevent effective use of diazepam to treat emergency seizures.   These drugs are effective for the emergency treatment of status epilepticus or cluster seizures.  They can also be useful as temporary therapy when seizures can be predicted, such as seizures precipitated by stress or sleep deprivation.

Clorazepate at a dosage of 0.5 to 1 mg/kg every 8 hours is sometimes effective when added to Phenobarbital.  Clorazepate serum levels tend to decrease with time so subsequent dose increases are usually necessary.  Measurement of peak and trough levels is recommended at 2 and 4 weeks.  Clorazepate can increase Phenobarbital concentrations which can lead to side effects, so Phenobarbital levels should also be checked at 2 and 4 weeks.

Dilantin (Phenytoin) Although Dilantin is extremely effective in treating human epilepsy, dogs metabolize this drug too quickly to maintain adequate blood levels.  In one clinical study only 1 in 77 epileptic dogs could be controlled with this drug.