Inflammation or infection of the tonsils is medically termed as tonsillitis. Tonsils are protective (lymph) glands that are situated on both sides in the throat. The tonsils constitute an important part of the body's immune system and are vital defense organs. They protect the body from bacteria and viruses by fighting these as soon as they enter the body (via the oral/nasal cavity). The tonsils along with adenoids are said to form the 'first line of defense' against infective organisms.

In the normal state, tonsils are pink in color (similar to their surroundings tissues) and about the same size. When the tonsils get inflamed, they become red, swollen and may develop pus pockets that start exuding a discharge. In cases with recurrent infections, the tonsils may become so swollen over a period of time so as to almost touch each other.

There are three types of tonsillitis:

Acute tonsillitis- An episode of tonsillitis that has been of recent origin is termed as acute tonsillitis. Acute tonsillitis can last for anywhere between four to ten days. It is commonly caused by virus or bacteria.

Sub-acute tonsillitis - This type of tonsillitis is commonly caused by the bacterium Actinomyces and lasts for more than 2 weeks.

Chronic, recurrent tonsillitis - Chronic tonsillitis is mostly caused by bacteria and lasts long periods. There may be enlargement of tonsils in cases of chronic infection. In case of recurrent tonsillitis, the patient tends to get episodes of tonsillitis repeatedly and remains symptom-free in between these episodes. It has been seen that recurrent episodes of tonsillitis can lead to scarring of the tonsils and renders them less capable of fighting against infections.Tonsillitis can affect people of all ages though it tends to be very common amongst children especially those between the ages of 5 to 10 years. No particular gender predilection is seen in cases of tonsillitis.