Tonsillitis on One Side: Causes and Duration

Yes, tonsillitis can occur on just one side of the throat. This condition, known as unilateral tonsillitis, is less common but entirely possible.

Typically, tonsillitis affects both tonsils because they are part of the body's immune system and often respond similarly to infections. However, certain factors can cause tonsillitis to appear on only one side.

When tonsillitis occurs on one side, it might be due to localized factors, such as:

• Isolated Bacterial Infection: Sometimes, a bacterial infection like Streptococcus (strep throat) might only affect one tonsil if the infection is more concentrated in that area.
• Asymmetrical Immune Response: The immune system might react more strongly on one side, leading to inflammation and infection in just one tonsil.
• Localized Irritation: Something specific, like a foreign object or an irritant that only touches one tonsil, could cause inflammation on one side.

While unilateral tonsillitis might not be as common as bilateral tonsillitis, it’s essential to recognize it and seek appropriate treatment if symptoms persist or worsen.

If you have an infection in only one of your tonsils, it could be due to several reasons. The most common reason is a localized infection that did not spread to the other tonsil. This situation might arise because of specific conditions that only affect one tonsil.

Here are some possible explanations for why only one tonsil might be infected:

• Tonsil Stones: Tonsil stones, or small calcifications, can form in the crevices of the tonsils. If a stone forms on only one side, it can lead to irritation and subsequent infection in that tonsil.
• Peritonsillar Abscess: Peritonsillar abscess, a complication of tonsillitis, is most often caused by group A beta-hemolytic streptococcus bacteria, as noted by Mount Sinai. This is a serious condition where an abscess forms near one of the tonsils, usually following a severe case of tonsillitis. This abscess typically occurs on one side and requires medical treatment.
• Localized Trauma or Injury: An injury to one side of the throat, such as from sharp food or an external force, might make that tonsil more susceptible to infection. The injury allows bacteria to enter the tissue, causing localized tonsillitis.

Understanding the cause of one-sided tonsillitis can help in managing the condition more effectively and preventing complications.

The duration of one-sided tonsillitis depends on several factors, including the underlying cause and how quickly treatment is initiated. Typically, tonsillitis caused by a viral infection, which accounts for about 70% of cases as stated by the Cleveland Clinic, might last for about 7 to 10 days.  In cases where the infection is bacterial, and antibiotics are prescribed, the condition might improve within a few days but could take up to 10 days to fully resolve.

Several other factors that influence the duration include:

• Presence of Complications: If a complication like a peritonsillar abscess develops, recovery could take longer, possibly requiring drainage and extended antibiotic therapy.
• Treatment Effectiveness: Prompt and appropriate treatment, including rest, hydration, and medication, can significantly shorten the duration of symptoms. If treatment is delayed, the infection might persist longer.

Monitoring the progress of one-sided tonsillitis is crucial. If symptoms do not improve or worsen within a week, it’s important to seek further medical advice to address potential complications or other underlying issues.