The US FDA approved Epidiolex® (cannabidiol, or CBD) for certain seizure syndromes in June, 2018, and in November, 2018, the DEA rescheduled it as a Schedule V controlled substance (the least restrictive). This will greatly facilitate clinical use and clinical trials of CBD in the U.S.
Note that there is little evidence at this point that CBD does anything good for tic disorders, though it’s a reasonable hypothesis. I’ve discussed the evidence here.