Please use this link to access this publication. Abstract Objectives Anecdotal reports and preliminary studies suggest a therapeutic potential of cannabis in Tourette syndrome. We report the case of a female patient suffering from treatment-resistant Tourette syndrome. Methods Guideline-directed antipsychotic treatment with risperidone and aripiprazole as well as pure delta-9-tetrahydrocannabinol had no significant effect on Tourette syndrome symptomatology. Results Following administration of a daily dosage of 10 mg delta-9-tetrahydrocannabinol combined with 20 mg cannabidiol (CBD), the patient showed a rapid and highly significant improvement in the Yale Global Tic Severity Scale. Conclusions It can be speculated whether the beneficial effects may rely on the...