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Definition of marijuana
Medical expert of the article
Last reviewed: 05.07.2025
Marijuana is a drug made from hemp ( Cannabis sativa ). It is a mixture of the above-ground parts of the plant. When the resin of the plant is extracted, a more active product is obtained - hashish. Cannabis (a general term for the psychoactive products of hemp) contains three main cannabinoids: cannabidiol, tetrahydrocannabinol, and cannabinol.
The main form of marijuana use is smoking. The high solubility of cannabinoids in lipids ensures their rapid uptake by lung surfactant. Cannabinoids have a number of effects characteristic of amphetamine, alcohol, sedatives, atropine and morphine. The psychological effects of cannabis include euphoria, oneiroid state, calmness and drowsiness. Intoxication appears almost immediately after smoking marijuana (after 2-3 puffs), reaches a maximum within 30 minutes and lasts from 2 to 4 hours (after 4 hours, the concentration of cannabinoids in the blood decreases). When taking the drug orally, the peak effect may be delayed up to 3-4 hours, but the effect is longer - 5-12 hours. The concentration of tetrahydrocannabinol in the blood 10 minutes after smoking 10 mg is 0.019-0.026 mg / l (0.06-0.083 μmol / l). Approximately 70% of the marijuana dose is excreted within 72 hours, in roughly equal proportions in urine and feces.
Cannabinoid intoxication is characterized by two important clinical signs: increased heart rate and conjunctival redness. The latter correlates well with the concentration of the active substance in the blood.
With frequent use of high doses of cannabis, some tolerance and mild withdrawal symptoms occur.
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