2. Cannabidiol - CBD also occurs in almost all varieties. Concentration range from nil (119,138), to about 95 percent of the total cannabinoids present. THC and CBD are the two most abundant naturally occurring cannabinoids. CBD is not psychotomimetic in the pure form (192), although it does have sedative, analgesic, and antibiotic properties. In order for CBD to affect the high, THC must be present in quantities ordinarily psychoactive. CBD can contribute to the high by interacting with THC to potentiate (enhance) or antagonise (interfere or lessen) certain qualities of the high. CBD appears to potentiate the depressant effects of THC and antagonise is excitatory effects (186). CBD also delays the onset of the high (183) but can make it last considerably longer (as much as twice as long). (The grass takes a while to come on but keeps coming on.) Opinions are conflicting as to whether it increases or decreases the intensity of the high, "intensity" and high" being difficult to define. Terms such as knock-out or sleepy, dreamlike, or melancholic are often used to describe the high from grass with sizeable proportions of CBD and THC. When only small amounts of THC are present with high proportions of CBD, the high is more of a buzz, and the mind feels dull and the body de-energised.