Gabapentin has analgesic effects and also anticonvulsant activity. The mechanism for its actions is not well understood. It can be a useful medication for the elderly dog or cat, but can also create problems if not used and dosed correctly. My most common recommendation for the use of Gabapentin in the elderly dog is for anxiety and sleep/wake reversal (awake, pacing and whining at night). It is also useful as a secondary medication for seizure control and is often prescribed for chronic pain relief. The latter use may be helpful for cats with arthritis. It does not appear to be helpful with acute pain although many veterinarians prescribe it for that purpose. 

Gabapentin should be given with caution when it is first used. If given at the recommended dosing schedule usually prescribed by veterinarians, it can create a “zombie” effect, where the dog or cat can barely function or can’t function at all. The dose is calculated based on the pet’s weight and, in most cases the instructions will be to give it 2 to 3 times daily. If this schedule is followed initially, the animal may become very drowsy to the point it cannot function normally. Of course, this will be very disconcerting to the pet caretaker, who may then stop giving the medication. Because this is such a common occurrence, I recommend only giving the Gabapentin at night for the first few treatments and then give at the recommended interval, but at a lowered dose during the day. The animal’s system will become accustomed to the Gabapentin after a few days. In cats, the initial dose may last for up to 36 hours with a gradual return to normal function. 

Gabapentin can extremely useful to decrease anxiety, and to help the dog or cat with cognitive problems to sleep better. It works well in about 85% of dogs and most cats. Some animals will develop diarrhea with it and it can’t be used in those cases. Occasionally, it can cause the animal to be hyper, or manic and can’t be used there either. Also, in a few animals it has no effect at all. In dogs, it is only effective for about 6 hours. For everyone to rest at night, it is best given around 10:30 to 11 P.M. It seems to have a longer effect in cats. A relatively uncommon problem that occurs with long term use in the dog has been recognized. This involves weakness in the hind legs. This syndrome, if caused by the Gabapentin, will improve when the medication is discontinued. It is important to note that the dose for Gabapentin should be gradually tapered if it is being used for seizure control. The drug should not be discontinued immediately unless it was just started and symptoms described above were seen.  Another important note from my experience: I don’t believe it should be used during the day in dogs with weakness or neurological problems as it seems to make the weakness worse rather than better.

There is another similar medication that may be useful in the dog and/or cat. Pregabalin (Lyrica) is a controlled medication currently approved for use in humans. It has not been cleared for used in animals. It is used off label as an anticonvulsant and to treat nerve or cancer pain in dogs and cats. Presently, it may be cost prohibitive and usually needs to be compounded. It can be given on an empty stomach every 12 hours and may cause drowsiness, loss of coordination and weakness. 

As with any medication, it is best to make sure you are aware of any side affects and what the expected results should be. I caution people all the time to be sure the medication is actually creating a positive result. If no results are seen after a period of time, then it may not be beneficial for the animal to continue giving the medication.