I found a brief mention thru medirabbit that states:
Levetiracetam is an anticonvulsant drug belonging to the class of pyrrolidines. It is used in human medicine, but is also administered to dogs, cats and rabbits suffering from seizures that are refractory to other anti-epileptic drugs. It can be used alone or in combination with phenobarbital
or potassium bromide.
— Based on this, it sounds like a safe anticonvulsant.
Found this on wagwalking.com, specifically about seizures in rabbits:
An anticonvulsant such as diazepam will be given intranasally and your pet monitored for signs of improvement. If the seizure does not cease phenobarbital sodium may be given via intravenous injection, repeat dosing may be required at 30 minute intervals. Your pet will be carefully monitored during this time. For animals who do not respond to this treatment, sedation under general anesthetic may be necessary. Propofol is commonly used for general anesthesia in rabbits and is short-acting with non-cumulative effects, however it may cause respiratory or cardiac depression so careful monitoring is essential.
…. I have no personal experience with it, but it seems to be known as a treatment in rabbits.
The answers provided in this discussion are for general guideline purposes only. The information is not intended to diagnose or treat your pet. Seek the advice of your veterinarian or a qualified behaviorist.