Lymph nodes are a part of the immune system, distributed throughout the body. The neck region, in particular, contains many groups of lymph nodes responsible for draining lymph fluid from the nose, throat, tonsils, and oral cavity.

When bacteria or viruses cause a sore throat, immune cells within these lymph nodes activate to identify and destroy the pathogens. This process causes the lymph nodes to enlarge, a condition known as reactionary lymph nodes, which typically appear under the jaw or on both sides of the neck.

Reactionary lymph nodes resulting from acute sore throats are usually small, soft or slightly firm, movable under the skin, and painful when pressed. They often appear alongside symptoms such as a sore throat, fever, cough, painful swallowing, or a runny nose, and gradually decrease in size as the inflammation is controlled.

In many cases, even after a sore throat has resolved, the lymph nodes may persist for a few weeks before returning to their normal size, as the immune system completes its response to the infection.

Patients should see a doctor if neck lymph nodes are hard, larger than 2 cm, and persistent. *Duy Anh*

You should seek medical examination for a specific diagnosis, as not all cases of swollen neck lymph nodes are benign. If a lymph node has a diameter of more than 2 cm, grows quickly, is hard, less mobile or fixed to surrounding tissue, and persists for more than 2-4 weeks without shrinking, a specialist examination is necessary to determine the underlying cause.

Signs such as prolonged high fever, severe sore throat, difficulty swallowing, difficulty breathing, or a red, hot, painful lymph node area may suggest complications like a peritonsillar abscess or a deep neck abscess. In some instances, persistent swollen lymph nodes can be related to tuberculous lymphadenitis, Epstein-Barr virus infection, lymphoma, or metastatic head and neck cancer.

Depending on the individual case, a doctor may order an ENT endoscopy, lymph node ultrasound, blood tests, or a lymph node biopsy if a cause other than a common infection is suspected. Treatment varies based on the underlying cause. Most viral sore throats resolve on their own after a few days with adequate rest, sufficient fluid intake, and gargling with salt water.

A doctor may prescribe antibiotics if a bacterial sore throat is suspected, especially Group A streptococcus. You should not self-medicate with antibiotics without a prescription, as this can increase the risk of antibiotic resistance, disrupt gut microbiota, and cause other adverse effects.

To reduce the risk of sore throats and swollen neck lymph nodes, individuals should practice hand hygiene, wear masks when necessary, limit contact with people who have respiratory illnesses, drink enough water, and avoid smoking. Getting sufficient sleep and thoroughly treating chronic ENT conditions such as tonsillitis, sinusitis, or allergic rhinitis also helps prevent sore throats that lead to swollen neck lymph nodes.

Master of Science, Doctor Nguyen Duc Minh

Department of Otolaryngology

Tam Anh Cau Giay General Clinic