While tonsillitis is uncommon in cats, when it does occur, it is usually the result of a bacterial infection and is treated with antibiotics. Other conditions can cause tonsillitis, which will require identification and treatment. If the condition becomes chronic or unresponsive to antibiotics, surgery to remove your cat’s tonsils may be recommended.

Tonsils are part of your pet’s lymphatic system. As part of the immune system, their function is to protect your pet from harmful bacteria and viruses. Tonsils can, however, become infected or enlarged, a condition referred to as tonsillitis. This condition can make normal functions like swallowing and breathing difficult. 

Symptoms of tonsillitis include:

As tonsillitis is often a secondary disorder, pet owners may also note symptoms of the primary disorder, such symptoms of a virus or a stomach condition.

Tonsillitis in cats is usually secondary to a primary condition. Possible causes of tonsillitis in cats include:

Your veterinarian will perform a complete physical examination including visual examination of the back of your cat’s mouth and throat to diagnose tonsillitis. As tonsillitis is usually caused by another underlying condition, your veterinarian will try to discover the conditions present in your cat. It will be important for you to give a complete medical history and describe any possible harmful exposures or incidents your cat may have had in order to identify what is causing the inflamed tonsils. Blood and urine tests may be conducted in an effort to identify other conditions present in your cat. In addition, x-rays may be ordered to determine if a chest infection or foreign object is present. Your veterinarian may also perform a throat swab and culture to determine what bacteria are present and determine the most effective antibiotic to counteract the infection.

If tumors of the tonsils are suspected, your veterinarian will perform a biopsy to check for cancerous cells.

Treatment will depend on the identified cause of the tonsil inflammation. If respiratory infection or bacterial infection is present, your veterinarian will prescribe a course of the appropriate antibiotic. Your veterinarian may also prescribe painkillers for a cat when the swollen tonsils are causing excessive pain and interfering with the animal's ability to swallow. If the case is severe and the animal has become dehydrated, fluids will be administered.

Prognosis is good if the cause can be identified and treated and your cat responds to the prescribed antibiotics. 

If tonsillitis becomes chronic in your cat, or if the inflamed tonsils are causing an obstruction of the throat, a tonsillectomy, in which the tonsils are removed, may be performed by your veterinarian.This is not usually necessary but may be required in some cases.

If surgery was required you should watch your pet for aspiration of fluids and hemorrhaging. Any non-dissolving sutures used will need to be removed post-surgery. Complete healing from surgery should occur in approximately two weeks During the recovery period, a soft food diet will be required until your pet is able to process hard food again. Any post-surgical medication and antibiotics should be administered as prescribed. It is possible for incompletely removed tissue to regrow. Should this occur and cause problems for your pet, you will need to return to your veterinarian for treatment. 

If your cat’s tonsillitis is being treated non-surgically with a course of prescribed antibiotics, ensure that the entire course is taken. Cats with tonsillitis should be given soft, mushy food while recovering so as not to further irritate their throat.

Your cat should have rest and a quiet environment to heal and recover.