Sir,I read with great interest the review article on Lhermitte's sign by Khare and Seth.[1] The sign occurs, inter alia, in multiple sclerosis, in traumatic lesions of the cervical cord, and in subacute combined degeneration. I agree that very few studies are available on Lhermitte's sign and there is need of more research in this particular field. In this current review, treatment with extracranial picotesla range pulsed electromagnetic fields was said to be effective. Neck brace and collar might also be prescribed by physical therapists, and exercises and relaxation technique were claimed to be helpful.I found that carbamazepine in a rather small dosage had an immediate symptomatic effect on the paresthesiae associated with Lhermitte's sign in three patients with multiple sclerosis.[2] In two of the patients, the symptoms reappeared when the treatment was discontinued. In two cases, the effect of the drug could be reproduced in several short series of treatment and was checked at each examination by letting the patient repeatedly bend his/her head forward in both a recumbent and sitting position. The therapeutic results in my cases resembled those obtained by carbamazepine in connection with the treatment of trigeminal neuralgia and spontaneous paroxysmal symptoms in multiple sclerosis such as painful tonic seizures and paroxysmal dysarthria.