Have Cat Questions? Ask a Cat Vet Online.
With cats, it's pretty easy to tell if they are not feeling well. There are two signs to watch for in them. First is a lack of appetite where they are not eating as much (or any) food at all. Second is isolation where they tend to go off and not socialize with you or your family, preferring to be under a bed, or in a closet or anywhere that you are not. If you see either of these 2 signs for more than 24 hours, it's a good idea to take your cat into the vet to see what's going on.
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I applied Frontline plus on my mail 10 year old cat