Cats often get by pretty well on their own, and they may recover from a mild illness even before you know they're sick. It's easy then, to overlook something that we are sure our cat will recover from. It's equally possible, however, that one or more of the following cat symptoms could indicate that your cat may have a significant illness or underlying condition as the cause. Pay very close attention to your cat's behavior, and if you see any of the following possible symptoms, take action right away.

Diarrhea - Diarrhea can be a sign of a more serious problem than just plain indigestion. It also causes dehydration, so do not let this go on for long without contacting your vet.

Vomiting - Vomiting is quite familiar to cats and cat owners. Hairballs are probably the most frequent cause of vomiting, and are usually of little concern.. But cats can into all manner of things, so it's not surprising they have a habit of giving some of those things back. They also have allergic reactions to plants and other items that can cause digestive distress. It might just be a hairball, but be alert to the possibility of a more serious problem if vomiting continues for any length of time. Poisons, intestinal disturbances, or serious illness could be the cause. Aside from the cause, vomiting can lead to dehydration. This is a serious condition that, untreated, can lead to death.

Lethargy - Cats sleep a lot, it's true. Lethargy, however, is one cat symptom that should not be ignored. It is an indication of a problem and a sign to watch out for. Since cats do sleep a lot, it may be hard to detect if they are sluggish. If your cat is normally bubbly and active, but suddenly begins sleeping in a corner for an entire day, something is probably wrong. I failed to catch this behavior change with one of my cats once for about a day since she was out in the open and seemed fine. By day two, however, she was too weak to jump, and she ended up needing IV fluids and an antibiotic.

Refusing to drink or eat - Not eating or drinking for extended periods, or outside of your cat's normal routine is suspect. Make sure you know your cat's eating and drinking habits well, and be alert to any changes. Animals who are ill often stop eating, so listen to what your cat is trying to tell you.

For the most part, cats are pretty sturdy creatures, and will recover from mild problems. There will be those times, however, when cat symptoms indicate a more serious situation or danger that must be treated. Be on the alert for those occasions.