RESUMEN
People with multiple sclerosis may present with a wide range of disease symptoms during the evolution of the disease; among these, spasticity can have a marked impact on their well-being and quality of life. Symptom control, including spasticity, remains a key management strategy to improve the patient's well-being and functional status. However, available drug therapies for spasticity sometimes have limited benefit and they are often associated with poor tolerability. Sativex is a 1:1 mix of 9-delta-tetrahydrocannabinol and cannabidiol extracted from cloned Cannabis sativa chemovars, which is available as an oromucosal spray. Clinical experience with Sativex in patients with multiple sclerosis is accumulating steadily. Results from randomized, controlled trials have reported a reduction in the severity of symptoms associated with spasticity, leading to a better ability to perform daily activities and an improved perception of patients and their carers regarding functional status when Sativex was added to the current treatment regimen. Adverse events such as dizziness, diarrhea, fatigue, nausea, headache and somnolence occur quite frequently with Sativex, but they are generally of mild-to-moderate intensity and their incidence can be markedly reduced by gradual 'uptitration'. In summary, initial well-controlled studies with Sativex oromucosal spray administered as an add-on to usual therapy have produced promising results and highlight encouraging avenues for future research.