Tonsillitis: Causes, Symptoms, and How It’s Treated

Manoj Kumar - B.Pharmacy

Published : Nov 11, 2024

Last Updated : Mar 05, 2026

A sore throat that makes swallowing painful, accompanied by fever and swollen glands, could be more than a common cold.

One possible cause is tonsillitis, an infection that inflames the tonsils at the back of the throat.

Tonsillitis is especially common in children but can affect people of any age.

It often develops when viruses or bacteria infect the tonsils, which normally act as part of the body’s immune defence system.

Most cases of tonsillitis improve within a week with proper care.

However, bacterial infections such as strep throat caused by Group A Streptococcus may require medical treatment to avoid complications.

Understanding the causes, symptoms, diagnosis, and treatment options for tonsillitis can help you recognise the condition early and manage it effectively.

What Is Tonsillitis?

Tonsillitis occurs when the tonsils become inflamed due to infection.

The tonsils are two oval-shaped lymphoid tissues located on each side of the throat.

Their main role is to trap germs entering through the mouth and nose, helping the body fight infection.

However, these same germs can sometimes infect the tonsils themselves, leading to swelling, pain, and irritation.

Tonsillitis can be viral or bacterial, and the severity of symptoms often depends on the cause.

Causes of Tonsillitis

The most common cause of tonsillitis is viral infection, but bacterial infections can also trigger the condition.

Viral Tonsillitis

Viruses responsible for common illnesses such as the cold or flu cause around 70% of tonsillitis cases.

Viral tonsillitis usually produces milder symptoms and often resolves on its own within a few days.

Common viruses linked to tonsillitis include:

• Rhinovirus (common cold virus)
• Influenza virus
• Adenovirus
• Epstein-Barr virus

Bacterial Tonsillitis

Bacterial infections are less common but often more severe and can be dangerous in a few cases.

The most frequent bacterial cause is Group A Streptococcus, which leads to strep throat.

Bacterial tonsillitis may cause stronger symptoms such as high fever, severe throat pain, and swollen lymph nodes.

Without treatment, it can sometimes lead to complications like rheumatic fever or kidney inflammation.

Symptoms of Tonsillitis

Tonsillitis symptoms can vary depending on the cause, but the condition typically affects children between preschool and their teenage years.

Common symptoms include:

• Fever
• Sore throat
• Red and swollen tonsils
• White or yellow patches on the tonsils
• Difficulty swallowing
• Bad breath
• Swollen lymph nodes in the neck
• Headache
• Neck stiffness or pain

Some children may also experience stomach pain or nausea.

Symptoms in Young Children

Young children who cannot describe their discomfort may show signs such as:

• Unusual fussiness
• Drooling due to painful swallowing
• Refusing food or drinks

How Tonsillitis Is Diagnosed

Doctors usually diagnose tonsillitis through a physical examination and laboratory tests.

Physical Examination

A doctor first examines the throat to check for:

• Swollen or red tonsils
• White patches or pus
• Signs of fever
• Enlarged lymph nodes in the neck

The doctor may also check the ears and nose to rule out other infections.

Throat Swab Test

A throat swab helps determine whether bacteria are responsible for the infection.

During this test, a cotton swab collects cells from the back of the throat.

The sample is tested for Group A Streptococcus bacteria, and results may appear within minutes or after laboratory analysis.

Blood Test

In some cases, doctors order a complete blood count (CBC) to check the levels of white blood cells.

This test helps determine whether the infection is viral or bacterial.

Doctors may also check for scarlet fever rash, which sometimes occurs alongside strep throat infections.

Treatment Options for Tonsillitis

Treatment for tonsillitis depends on whether the infection is viral or bacterial.

Treatment for Viral Tonsillitis

Viral infections usually resolve without antibiotics, as they are different and need different treatment.

Doctors often recommend supportive care, including rest, hydration, and pain relief.

Over-the-counter medicines such as acetaminophen or ibuprofen may help reduce throat pain and fever.

Treatment for Bacterial Tonsillitis

If the infection is caused by bacteria, doctors may prescribe antibiotic medicines to eliminate the bacteria and prevent complications.

Common antibiotics used include:

• Penicillin
• Cephalosporins
• Clindamycin

It is important to complete the full course of antibiotics, even if symptoms improve early.

Tonsillectomy for Recurrent Tonsillitis

For people with frequent or severe tonsillitis, doctors may recommend tonsillectomy, a surgical procedure to remove the tonsils.

This option is usually considered when infections occur repeatedly and interfere with daily life.

Preventing Tonsillitis

Since tonsillitis spreads through germs, maintaining good hygiene is essential.

Simple preventive steps include:

• Washing hands frequently
• Avoiding close contact with infected individuals
• Not sharing utensils or drinks.
• Covering the mouth when coughing or sneezing

These measures help reduce the risk of infections that can lead to tonsillitis.

Conclusion: All About Tonsillitis

Tonsillitis is a common infection that causes inflammation of the tonsils, usually due to viral or bacterial infections.

While most cases resolve within 7 to 10 days, bacterial infections like strep throat may require antibiotics to prevent complications.

Recognising symptoms early and seeking medical advice when necessary can ensure effective treatment and faster recovery.

Maintaining good hygiene and following proper medical guidance are key to managing and preventing tonsillitis.