Cannabis Drug Driving Limit = 2 µg/L
Delta-9-Tetrahydrocannabinol is the principal psychoactive constituent (or cannabinoid) of cannabis. THC has mild to moderate analgesic effects, and cannabis can be used to treat pain. Other effects include relaxation, alteration of visual, auditory, and olfactory senses, fatigue, and appetite stimulation. THC is effective against vomiting and nausea. It may acutely reduce aggression and increase aggression during withdrawal.
It is found in prescription drug Sativex which is a prescription drug for multiple Sclerosis.
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