24 patients experiencing central lesion pain due to multiple sclerosis were randomly assigned to receive either dronabinol (maximum of 5mg twice per day) or placebo for 3 weeks. They then underwent a washout period of at least 3 weeks, and were crossed-over to receive the other intervention for 3 weeks. Patients were assessed on the median spontaneous pain intensity, radiating pain intensity, pain relief, health-related quality of life, various quantitative sensitization tests, and the incidence of adverse events. Results demonstrated dronabinol treatment efficacy in reducing spontaneous pain intensity, radiating pain intensity, and pressure-evoked pain. Dronabinol treatment also raised more adverse events than placebo, but no adverse events led to study drop-out.