AbstractEssential thrombocythemia (ET) is a myeloproliferative disorder characterized by isolated overproduction of platelets, thrombohemorrhagic complications, and a median age of 50–60. When it occurs in younger patients, the incidence of complications has been reported to be quite low, with a good long‐term prognosis. We report a retrospective review of 13 patients with ET between the ages of 22 and 35 in which 11 were symptomatic at diagnosis, with only one remaining asymptomatic during follow‐up. Three patients presented with potentially life‐threatening complications (two myocardial infarctions, one stroke), although no deaths were observed. The majority of the nonlife‐threatening complications were vaso‐occlusive in nature, including erythromelalgia and transient neurologic symptoms. We conclude that ET in young adults is not always a benign disease and that potentially life‐threatening complications are not rare. The optimum approach to treatment in this or any other age group rema