The primary effects of cannabinoids are exerted in the central nervous system and expressed by a decreased motivation for physical effort, impairment of psychomotor performance as well as short-term memory and perception. In addition to psychological effects marijuana induces tachycardia, bronchodilation and an increased blood flow to the limbs. In users with some cardiovascular diseases (hypertension or atherosclerosis) the increased heart rate after cannabinoids consumption would have a serious medical adverse effect. Smoking of hashish or marijuana can induce the development of bronchitis and lung pathology.

Chronic consumption of cannabinoids could lead to destruction of CB1 receptors in the brain resulting in reduced blood flow and decreased glucose and oxygen supply to the brain tissues. The main results are attention deficits, memory loss, and impaired learning ability.

The various effects of cannabinoids on the central nervous system include:

• euphoria,
• panic attacks,
• impaired comprehension,
• altered sense of time,
• paranoia,
• anxiety,
• altered cognition,
• impaired learning,
• memory,
• perception,
• judgement,
• depersonalization,
• confusion,
• amnesia,
• and hallucinations.

Acute effects of hashish and marijuana are low with negligible risk of lethal intoxication. Addiction to the cannabinoids may be related to the dose applied.