12.4 : 中枢神经兴奋剂和致幻剂：可卡因、安非他明和大麻素

CNS stimulants are agents that modulate neuronal activity. These three stimulants each have a distinct structure, mechanism, and effect.

Cocaine, an alkaloid derived from coca plants, increases extraneuronal dopamine concentrations by inhibiting its reuptake.

It enhances alertness, elevates heart rate and blood pressure, and induces euphoria at higher doses.

Prolonged use leads to involuntary motor activity, paranoia, and violence. Cocaine addiction carries risks like cardiac arrhythmias, cerebral vasoconstriction, and seizures, necessitating rehab, psychotherapy, and pharmacotherapy.

Amphetamines, particularly methamphetamine, share similar mechanisms and abuse potential as cocaine. They treat conditions like narcolepsy and ADHD.

Cannabinoids, such as marijuana and its psychoactive alkaloid Δ⁹-THC, act on the brain's CB₁ receptors.

Cannabinoid intoxication impairs cognition and memory. However, Δ⁹-THC has medicinal uses, such as reducing intraocular pressure in glaucoma, inducing muscle relaxation, and possessing antiemetic properties.