What caused cat’s episode?

Dear Dr. John,

My two cats are 14-year-old. About a week ago, one of them was standing on the table next to me when suddenly her pupils dilated wide, and she appeared to be unsteady on her feet. I was concerned and thought of taking her to an emergency hospital but within no more than 30 seconds it passed. She returned to normal, and she has remained that way since. What could it have been? She is otherwise acting like her old self and other than seemingly at odds with her sister for about a day afterwards all is good. Should I still be concerned or do anything else at this time? J.A.

Dear J.A.,

There is no way of knowing whether or not there is an underlying problem that presented as a short-term passing episode. Lots of possibilities come to mind and there is even the possibility that there is nothing wrong at all.

Pupils dilate in low light, in cases of fear or aggression, when cats are poisoned, in cases of high blood pressure, with brain trauma or masses, seizures, low blood sugar or electrolyte imbalances, and more. It may be accompanied by unsteadiness or imbalance as well. I list them not to frighten you but to give you an idea of the myriad of options. If I had to guess, she may have had a mild mini seizure based on what you described, that may be insignificant.

Now that a week or so has passed and she is acting within normal limits, I suspect there is no reason to panic but nonetheless, I would have her seen by your veterinarian for a full physical examination with a neurological assessment and bloodwork. Be sure to give them a good history and description of your observations. Any underlying problems would likely be diagnosed with an exam and basic diagnostics. As for the sister cats being at odds briefly, when things go awry in a home with more than one cat, there is sometimes a lack of recognition between cats of the other(s) until things normalize. Seems like all is well now and good luck with her being checked out.