Cannabis

Name:

Cannabis, marihuana, pot, weed, 420

Effects: 

'High' feeling, change in perception, euphoria, increased appetite, muscle relaxation. 

Side effects: 

Anxiety, panic, impaired attention and memory, psychotic symptoms, temporal disintegration, dry mouth, eye reddening, increased heart rate. 

Mechanism of action:

Tetrahydrocannabinol (THC) acts on G-protein coupled receptors CB1 (brain) and CB2 (peripheral nerve system), inhibiting secondary messenger system (adenylate cyclase) in a dose dependant manner. CB 1 receptor activation in the brain indirectly increases dopamine release. 

Substance and dosage:

Herbs, paste, oil (medicinal). Usually smoked, can be used to make tea. 

Overdosage:

No lethal overdose due to THC has been reported in humans. Signs of overdosage may include rapid heartbeat, anxiety attacks, and severe paranoia. 

Rimonabant (Acomplia, Zimulti) is an anti-obesity drug and CB1 receptor inverse agonist, countering the effects of THC. However, it was withdrawn worldwide in 2008 due to serious psychiatric side effects. It was never approved in the United States.