Recurrent bilateral brachial plexus neuritis following rapid semaglutide-induced weight loss: a case report

Background: Brachial plexus neuritis, or Parsonage–Turner syndrome, is an uncommon neuropathy marked by acute pain followed by weakness, often triggered by infection, vaccination, trauma, or metabolic stress but the exact cause of this disease remained unknown. Semaglutide is widely used for the treatment of type 2 diabetes and obesity. With its increasing use, there have been reports suggesting a possible association with neuropathies. Currently, there is no information suggesting a possible association between the use of semaglutide and brachial plexus neuritis. Case presentation: A 39-year-old man with a prior episode of unilateral brachial neuritis developed recurrent bilateral upper limb weakness after an eight-month, 70-pound semaglutide-associated weight loss. He presented with bilateral radial sensory loss, finger extensor paralysis, right triceps weakness and decreased grip strength on the left side. Corticosteroids provided pain relief, but motor and sensory deficits persisted despite physiotherapy. Conclusion: This case highlights a temporal association between rapid pharmacologic weight loss and recurrent idiopathic brachial plexus neuritis, emphasizing the importance of gradual, nutritionally supported weight reduction and vigilance for neuromuscular complications during GLP-1 receptor agonist therapy.