My little boy has three swollen lymph nodes down one side of his neck (starts in his hair line then goes down to mid neck) for over 3 weeks now. how long can they take to go down? dr has seen them and said they are just reactive lymph nodes?

Movable small lymph nodes (diameter less than 1.5 cm) are often found in the anterolateral neck in children. They may not disappear but may get smaller and stay. Chance of malignancy, e.g., lymphoma, is extremely low.

Lymph nodes are little serum strainers that specialize in removing debris from the clear body serum. They enlarge when they are active and shrink back to resting size when quiet,Bug bites, viruses, regional infection, skin rashes are part of what triggers these to grow and shrink over weeks/months. Detection is easier over the head where they are not buried in muscle or fat.