Fifty-two patients with chronic vertigo associated with underlying circulatory insufficiency were treated with 3-6mg of Dihydroergotamine daily for about 4 weeks and followed for changes in (1) subjective vertigo, (2) vestibular function, (3) signs of disorders of the inner ear and central nervous system, (4) predisposing conditions, and (5) associated symptoms. Each sign, symptom or abnormal test result was graded as mild, moderate or severe. The therapeutic results were rated on a 5-point scale: marked, moderate, or slight improvement, no change or aggravation in comparison to the pretreatment level.(1) The improvement rate for subjective vertigo was 69%.(2) For vestibular function, the improvement rate was 25% for voluntary nystagmus, 48% for the Romberg test, 56% for the writing test, a test of deviation reaction, and 52% for the stepping test.(3) Those with disorders of the inner ear and central nervous system showed no improvement by audiometry, but in the test for nystagmus caused by labyrinthine stimulation, the improvement rate was 38%.(4) In regard to predisposing conditions, the improvement rate for OD symptoms was 73% and that for Schellong's test was 55%.(5) Relief of associated symptoms was high for nausea and vomiting (70%) and headache (50%).