Effects of THC
THC acts on pathways found in many parts of the body, including the brain, heart, lungs and spinal cord. These pathways are called cannabinoid receptors.
Most studies so far have focused on how THC affects the brain. Because the endocannabinoid system is so complex, much about the short and long-term effects of THC remains poorly understood.
THC causes users to feel happy, or euphoric, by increasing levels of dopamine in the brain. Along with feelings of euphoria, THC is known to stimulate appetite and induce feelings of relaxation and fatigue.
THC can affect motor coordination and cognitive performance. It may also alter sights, sounds and tastes.
THC causes a number of physiological changes as well. Common changes include reduced eye pressure, dry mouth, increased heart rate and muscle relaxation.
The effects of THC usually last 1-2 hours when smoked or 4-10 hours when eaten.
Studies on the long-term effects of marijuana use have produced inconsistent results. There is some evidence that frequent use may result in the following:
- Short-term memory loss
- Lower mental aptitude scores
- Mania or psychosis
- Lack of motivation
But studies have yet to provide conclusive evidence of any negative, long-term effect of THC intake.
THC poses no risk of lethal overdose. Studies show it has a therapeutic index (lethal dose to therapeutic dose ratio) of 40,000:1.
Read More: Can You Overdose on Marijuana?
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