Yes, it does narrow suspected causes, and thank you for your additional information! : )
If this is happening once or twice a week, is it right after eating and does she throw up mainly undigested food and do you ever see any hair in with it? Does it ever look like a long, sort of 'braid' shape of hair in the middle surrounded by some liquid?
If she doesn't throw up right after eating, does it look like digested food with some fluid?
Sometimes, cats will regurgitate right after or soon after eating if they eat too fast, take in too much air, or their stomach has been empty for quite a few hours and starts producing acid.
To avoid this: make sure she has food available at all times (free-feed with dry food) or, if she's fed on a schedule, feed smaller meals more frequently during the day and make sure there's dry food down at night. Raising up the food dishes to chest height will help with digestion.
If she's eating too fast, try placing a clean, unused golf or ping pong ball in the middle of the dish of dry food and for wet food, serve on a flat plate, not in a bowl, and mash down the food with a fork so it's not mounded up in the middle. If the food is evenly distributed on the plate, this will slow down the eating.
If a cat's stomach is empty for too many hours, this causes it to produce acid, which in turn causes nausea, and when she finally eats, she will eat quickly, being pretty hungry, and the food will hit the stomach and the nausea will cause regurgitation. Regurgitation, as opposed to vomiting, simply means throwing up undigested food almost immediately after eating.
Even if her stomach isn't very empty when she eats, she still might be suffering from acid reflux, just as humans do. Pepcid AC is sometimes recommended by vets to help deal with this problem, but please don't give her any human OTC medications without direction from your vet, first!
Some foods contain corn, wheat and/or gluten, which are common allergens for cats. Even if she doesn't throw up all the time, she could still have a food allergy or sensitivity to one or more ingredients in her food. High quality cat foods by companies like Wellness, Nutro, Felidae and Innova, don't contain 'fillers' as mentioned above.
Do you ever offer milk as a treat? This can cause digestive upset, as most cats are lactose intolerant and it will cause vomiting and/or diarrhea. Does she get any human food treats? My sister's cat vomits every time she's offered canned tuna!
If you feel she may be vomiting hairballs, or it's possible that some of her own fur is 'tickling' her throat causing her to gag and then vomit, help her by combing/brushing her a couple of times daily, to help remove excess dead fur which she would risk ingesting when self-grooming.
Is it possible she's nibbling any houseplants (real or fake) or anything else in the house that you're not aware of? Do you see anything strange in the vomitus?
Well, I hope all of these suggestions will help you determine the cause and fix the problem, so she stops vomiting. Some cats are just 'vomiters' and others are not. My present cat is NOT a vomiter--not even hairballs--but recently had a bout of frequent, daily vomiting which necessitated a trip to the vet.
Please keep me posted on how she's doing. Thanks!
Cher
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