I'm sorry if I sound too paranoid with my question, today my cat was sneezing continuously for a few minutes and it scared me a bit because it's never happened before, he's still behaving the usual, but should I be worried?
Im also pretty anxious about taking him to the vet cause where I've had too many bad experiences with the vets where I live.
Sneezing is a natural reflex and some sneezing once in a while is perfectly normal.
A bout of sneezing for several minutes is not exactly "normal", but it's not an emergency either. The cat may have had something like dust or a fiber stuck in its nose, which took a while to clean out. Or it might have reacted to a scent of an air refresher, scented candle or cleaning product. But it also may have a respiratory infection and this was just the first bout of sneezing.
If I were in your shoes, I'd observe the cat more carefully than usual. Is the breathing as effortless as ever or does it sound snotty or heavy in any way? Does the cat sleep more than usual or eat less? Does it sneeze again? If yes, it's time to schedule a visit to the vet.
If there was something with a strong scent (especially with essential oils) in the vicinity of the cat when it happened, please remove the object or don't use the product anymore. Most essential oils are toxic to cats and can cause coughing and sneezing. Read more here and here.
