THC, an active ingredient in cannabis, is known to block the activity of the neurotransmitter GABA in the brain. This leads to a short-term increase in dopamine activity, resulting in a high.
However, frequent or long-term cannabis use can cause the body to shut down dopamine receptors, lowering active dopamine levels for extended periods of time.
Low dopamine levels are associated with serious mental and physical disorders and can leave you feeling depressed and unable to take pleasure in your daily life.