Throat blisters are fluid-filled sacs or sores that can develop on the tonsils, the back of the throat, or the roof of the mouth. They vary in size and appearance, often indicating an underlying health condition. While these blisters can cause discomfort, many of their causes are benign, though some situations necessitate medical attention.
Infectious Causes of Throat Blisters
Viruses are a common cause of throat blisters. Herpangina, for instance, is a viral infection often caused by coxsackieviruses, predominantly affecting children. This condition presents with small, painful blisters or ulcers in the back of the mouth, throat, and on the tonsils, typically appearing white or gray with a red border. The virus spreads easily through respiratory droplets, saliva, direct contact with fluid from a sore, or through fecal matter.
Hand-Foot-and-Mouth Disease, also caused by coxsackieviruses, results in painful, blister-like lesions in the mouth and throat, along with a rash on the hands and feet. The virus transmits through direct contact with nasal and throat discharges, blister fluid, or feces of infected individuals. Herpes Simplex Virus (HSV) can also extend to the throat, causing painful blisters or ulcers. It spreads through direct oral contact or contact with infected saliva.
The Varicella-Zoster Virus (VZV), causing chickenpox and shingles, can also manifest as throat blisters. Chickenpox typically presents with an itchy, blistering rash that can appear in the throat, while shingles, a reactivation of VZV, can also cause painful lesions. Both chickenpox and shingles can spread through direct contact with fluid from blisters or airborne particles.
Bacterial infections are less common, but severe tonsillitis or pharyngitis can lead to ulcerations resembling blisters. These infections can cause significant inflammation and pain in the throat. When present, such bacterial causes usually require specific antibiotic treatment.
Fungal infections can also contribute to throat lesions, although they typically do not present as fluid-filled blisters. Oral thrush, or candidiasis, caused by an overgrowth of Candida yeast, often appears as creamy white patches or spots in the mouth and throat. These patches may sometimes lead to irritated or sore areas.
Non-Infectious Causes of Throat Blisters
Non-infectious factors can also cause throat blisters or similar lesions. Physical irritation or trauma is a common cause. Consuming very hot foods or liquids can scald the delicate tissues of the throat, leading to the formation of blisters. Similarly, sharp food items or accidental injury can cause localized trauma, resulting in blister-like sores.
Exposure to chemical irritants, such as certain fumes or substances, can also provoke an inflammatory response in the throat, manifesting as irritation or lesions that might resemble blisters. Allergic reactions to specific foods, medications, or environmental allergens can also trigger swelling and blister-like lesions in the throat.
Certain autoimmune conditions, though rare, can cause blistering on mucous membranes, including those in the throat. Pemphigus and bullous pemphigoid are examples of such disorders where the immune system mistakenly attacks healthy tissues, leading to the formation of fragile blisters that can rupture and form painful sores. Gastroesophageal reflux disease (GERD) can also contribute to throat irritation. The frequent backflow of stomach acid into the esophagus and throat can cause chronic inflammation and ulcerations, which might be mistaken for blisters.
Accompanying Symptoms and When to Seek Medical Care
Throat blisters often appear alongside other symptoms, which can help in identifying the underlying cause. Common accompanying symptoms include a sore throat, making swallowing difficult (dysphagia), fever, and swollen lymph nodes in the neck. Individuals may also experience headache, body aches, and a reduced appetite. The specific combination and severity of symptoms can vary depending on the cause.
It is important to seek medical care if certain symptoms arise. Prompt consultation with a healthcare provider is advised if there is severe pain or difficulty swallowing that prevents eating or drinking, or if a high fever (above 102°F or 39°C) is present. Difficulty breathing or shortness of breath requires immediate medical attention. Signs of dehydration, such as reduced urination, dry mouth, or unusual lethargy, also warrant medical evaluation.
Medical attention should also be sought if the blisters are spreading, worsening, or do not show improvement after a few days. The appearance of blisters accompanied by a rash elsewhere on the body, particularly on the hands or feet, is another reason to consult a doctor. Individuals with weakened immune systems should seek medical care for any throat blisters. Recurrent or unexplained throat blisters also indicate a need for professional assessment to determine the cause and appropriate treatment.