Cannabis

The effects of cannabis are caused by cannabinoids, most notably the chemical substance tetrahydrocannabinol (THC).

Cannabis has both psychological and physiological effects on the human body. Because it is psychoactive, it is an

 illegal substance in most of the world^{[citation needed]}. Five European countries, Canada, and eighteen US states^[1] have legalized medical cannabis if prescribed for nausea, pain or the alleviation of symptoms surrounding chronic illness.^{[citation needed]}

Acute effects while under the influence can include euphoria and anxiety.^[2][3] Concerns have been raised about the potential for long-term cannabis consumption to increase risk for schizophrenia, bipolar disorders, and major depression,^[4][5] but the ultimate conclusions on these factors are disputed.^[6][7] The evidence of long-term effects on memory is preliminary and hindered by confounding factors.^[8][9] For thousands of years people have said that cannabis has religious and spiritual effects.^[10]