A case of vertebral artery dissection and consequent basilar artery thrombosis in a 6-year-old patient is reported. The patient was treated with subcutaneous low-molecular-weight heparin at therapeutic doses (enoxaparin, 100 IU/kg twice daily) for 3 weeks, then reduced to 2,000 IU/day for 3 more weeks. After this time a magnetic resonance angiogram was obtained that showed complete recanalization of the left basilar artery. Enoxaparin proved to be a safe and useful therapy for thrombosis accompanying vertebral artery dissection.