Why is my cat grooming himself so much lately?

 Excessive grooming of the fur is a common problem in cats.  Some times cats will create bald patches on themselves, and sometimes cats can groom themselves to the point of created large sores, most commonly on the belly or the inside of the back legs.  Cats that excessively groom themselves can do so for a number of reasons.  The top 2 reasons are allergies and anxiety.  Cats with allergies will often have other symptoms of allergies, like little scabs around the head and neck, or vomiting.  For cats that groom themselves to the point of sores, this is typically allergy related.  Cats can be allergic to things in their environment, or something in their food.  About 30% of cats with allergies will have a food allergy.  I often will recommend a hypoallergenic food trial in cats that excessively groom to see if that helps resolve the symptoms.  There are many great medications for cats that have allergies and overly groom.  My favorite for cats is a drug called, Atopica.  For those cats that groom for behavioral reasons, trying to determine the reason for an underlying anxiety can be helpful.  Is the cat getting "bullied" in the house, or is she not getting enough mental stimulation?  Your veterinarian can help you work through your cat's anxiety, and sometimes an anti-anxiety medication will be prescribed.