When it comes to trying CBD for anxiety or PTSD it is important that the effects are immediate so a CBD product that can be inhaled or smoked is generally the best product to try for dealing with anxiety or PTSD attack. This would include products like CBD flower, CBD cartridges or a CBD Inhaler. For prevention, an edible is best because the duration of edibles lasts much longer than products that are inhaled. While they work quickly the effects do not last long.