Causes of Tonsillitis Explained
Know about tonsillitis, what causes it, symptoms, how to prevent it, can it be serious and learn when to seek doctor’s advice.

Written by Dr. Shaik Abdul Kalam
Reviewed by Dr. Rohinipriyanka Pondugula MBBS
Last updated on 12th Aug, 2025

Introduction
Tonsillitis is a common condition that affects people of all ages, especially children. If you or your child have ever experienced a sore throat, difficulty swallowing, or swollen tonsils, you may have had tonsillitis. Understanding what causes tonsillitis can help you take the right steps to prevent it and seek timely treatment.
What Is Tonsillitis?
Tonsillitis is the inflammation of the tonsils. The two small glands located at the back of your throat. These glands act as part of your immune system, helping to trap bacteria and viruses that enter through your mouth. However, sometimes they themselves get infected, leading to swelling, pain, and discomfort.
Consult ENT specialist for Personalised Advice
Common Causes of Tonsillitis
Tonsillitis can be caused by both viral and bacterial infections. Here’s a breakdown of the most common causes:
1. Viral Infections
Most cases of tonsillitis are caused by viruses, including:
- Common cold viruses (Rhinovirus, Adenovirus)
- Flu virus (Influenza)
- Epstein-Barr virus (which also causes mononucleosis or "mono")
- Herpes simplex virus
- Viral tonsillitis is usually milder than bacterial tonsillitis and often resolves on its own with rest and home care.
2. Bacterial Infections
The most common bacterial cause of tonsillitis is Group A Streptococcus (Strep throat). Other bacteria, such as Staphylococcus aureus, can also lead to tonsillitis.
- Bacterial tonsillitis tends to cause more severe symptoms, including high fever, pus on the tonsils, and swollen lymph nodes.
- If left untreated, it can lead to complications like rheumatic fever or kidney inflammation.
3. Other Causes
- Fungal or yeast infections (rare but possible in people with weakened immune systems)
- Chronic irritation (due to smoking, pollution, or acid reflux)
- Recurrent infections (leading to chronic tonsillitis)
How Does Tonsillitis Spread?
Tonsillitis is contagious and spreads through:
- Airborne droplets (when an infected person coughs or sneezes)
- Direct contact (sharing utensils, kissing, or touching contaminated surfaces)
- Poor hand hygiene (not washing hands after touching the nose or mouth)
Symptoms of Tonsillitis
Common signs include:
- Sore throat
- Red, swollen tonsils (sometimes with white or yellow patches)
- Difficulty swallowing
- Fever and chills
- Bad breath
- Ear pain
- Swollen lymph nodes in the neck
How to Prevent Tonsillitis?
While you can’t always avoid tonsillitis, these steps can lower your risk:
- Wash hands frequently with soap and water.
- Avoid close contact with people who have throat infections.
- Don’t share utensils, drinks, or toothbrushes.
- Strengthen your immune system with a balanced diet, exercise, and adequate sleep.
- Stay hydrated to keep your throat moist and less prone to infections.
- Quit smoking and avoid exposure to secondhand smoke.
When to See a Doctor?
Most cases of viral tonsillitis improve within a week with home care. However, consult a doctor if you experience:
- Severe throat pain that lasts more than 48 hours
- Difficulty breathing or swallowing
- High fever (above 101°F or 38.3°C)
- Persistent bad breath or pus on the tonsils
- Recurrent tonsillitis (multiple episodes in a year)
If bacterial tonsillitis is suspected, your doctor may recommend a throat swab test to confirm the presence of strep bacteria. Antibiotics may be prescribed if the infection is bacterial.
Home Remedies for Relief
While recovering, try these soothing remedies:
- Gargle with warm salt water (helps reduce swelling).
- Drink warm fluids (herbal teas, broth, honey-lemon water).
- Use a humidifier to keep the air moist.
- Take over-the-counter pain relievers (like ibuprofen or acetaminophen) after consulting a doctor.
- Get plenty of rest to help your body fight the infection.
Can Tonsillitis Be Serious?
- In rare cases, untreated bacterial tonsillitis can lead to complications like:
- Peritonsillar abscess (a pus-filled pocket near the tonsils)
- Rheumatic fever (affecting the heart)
- Post-streptococcal glomerulonephritis (a kidney condition)
- If you have frequent tonsillitis infections, your doctor may discuss tonsillectomy (surgical removal of the tonsils) as a long-term solution.
Final thoughts
Tonsillitis is common, but understanding its causes and taking preventive steps can help you stay healthy. With the right care, most cases recover quickly, so listen to your body and seek help when needed.
Consult ENT specialist for Personalised Advice
Consult ENT specialist for Personalised Advice

Dr. Rohit Agrawala
Ent Specialist
4 Years • MBBS, MS ( ENT )
Bhubaneswar
Apollo Hospitals Old Sainik School Road, Bhubaneswar

Dr. Chanchal Pal
Ent Specialist
36 Years • MBBS, MS (ENT, Head & Neck), PG Certificate (Hospital Administration)
Delhi
Apollo Hospitals Indraprastha, Delhi
(50+ Patients)

Dr. Nishant Rana
Ent Specialist
8 Years • MBBS. MS ENT
Delhi
Apollo Hospitals Indraprastha, Delhi
Dr. Ashwani Kumar
Ent Specialist
11 Years • MBBS, DNB (Otorhinolaryngology)
Delhi
Apollo Hospitals Indraprastha, Delhi
(25+ Patients)
Dr. Vinita Bhagia
Ent Specialist
26 Years • MBBS, M.S.(ENT), FRCS,
Ahmedabad
Apollo Hospitals Gandhinagar, Ahmedabad
(75+ Patients)
Consult ENT specialist for Personalised Advice

Dr. Rohit Agrawala
Ent Specialist
4 Years • MBBS, MS ( ENT )
Bhubaneswar
Apollo Hospitals Old Sainik School Road, Bhubaneswar

Dr. Chanchal Pal
Ent Specialist
36 Years • MBBS, MS (ENT, Head & Neck), PG Certificate (Hospital Administration)
Delhi
Apollo Hospitals Indraprastha, Delhi
(50+ Patients)

Dr. Nishant Rana
Ent Specialist
8 Years • MBBS. MS ENT
Delhi
Apollo Hospitals Indraprastha, Delhi
Dr. Ashwani Kumar
Ent Specialist
11 Years • MBBS, DNB (Otorhinolaryngology)
Delhi
Apollo Hospitals Indraprastha, Delhi
(25+ Patients)
Dr. Vinita Bhagia
Ent Specialist
26 Years • MBBS, M.S.(ENT), FRCS,
Ahmedabad
Apollo Hospitals Gandhinagar, Ahmedabad
(75+ Patients)