What is Extended-release Levetiracetam?

Heidi Barnes Heller, DVM, DACVIM (Neurology), clinical associate professor of neurology/neurosurgery at the University of Wisconsin-Madison School of Veterinary Medicine, conducted a study on the efficacy of extended release levetiracetam in cats. Here, she explains how the drug works.

"Extended-release are the ones that we give as a pill they are formulated by pharmaceutical companies into a certain formulation that allows them to have extended release properties. They're taken orally but they are extended release because they are more slowly released into the body, in theory, thus allowing you to provide a lower dosing frequency—so the interval between dosing is less.

So going from a standard release, which is not extended release, that's 3 times a day dosing, we've been able to go down to once a day dosing use an extended release pill in cats for this particular drug, which is called levetiracetam. It is a pre formulated drug made by the pharmaceutical company, if you modify it, break it, chew it, crush it, you ruin or disrupt the extended release. So you have to be careful how you handle those pills. That also means that there's only several sizes made and a cat is wee tiny, so up until this point, we really haven't used extended release for cats because they oftentimes don't fit the dosing size for that particular milligram.

And so for example, we'll use extended release levetiracetam in cats and the dose they should be taking for an average or maybe slightly large, 5 kilogram cat would be something in the range of 50 to 60 milligrams three times a day, and so that's about 20 milligrams per kilogram is the dose that we use. To use extended release they're getting about a 100 milligrams per kilogram, which is 500 milligrams per dose, so a significantly higher dose but it extends out how its released and so you don't have as much of a worry about toxicity, at least in our studies."