Division on Substance Abuse, New York Psychiatric Institute, New York, NY, USA.
Exp Clin Psychopharmacol. 2013 Aug;21(4):287-93. doi: 10.1037/a0033661.
Active marijuana produces significant subjective, psychomotor, and physiological effects relative to inactive marijuana, yet demonstrating that these effects are dose-dependent has proven difficult. This within-subject, double-blind study was designed to develop a smoking procedure to obtain a marijuana dose-response function. In four outpatient laboratory sessions, daily marijuana smokers (N = 17 males, 1 female) smoked six 5-s puffs from 3 marijuana cigarettes (2 puffs/cigarette). The number of puffs from active (≥5.5% Δ⁹-tetrahydrocannabinol/THC) and inactive (0.0% THC) marijuana varied according to condition (0, 2, 4, or 6 active puffs); active puffs were always smoked before inactive puffs. Subjective, physiological, and performance effects were assessed prior to and at set time points after marijuana administration. Active marijuana dose-dependently increased heart rate and decreased marijuana craving, despite evidence (carbon monoxide expiration, weight of marijuana cigarettes post-smoking) that participants inhaled less of each active marijuana cigarette than inactive cigarettes. Subjective ratings of marijuana "strength," "high," "liking," "good effect," and "take again" were increased by active marijuana compared with inactive marijuana, but these effects were not dose-dependent. Active marijuana also produced modest, non-dose-dependent deficits in attention, psychomotor function, and recall relative to the inactive condition. In summary, although changes in inhalation patterns as a function of marijuana strength likely minimized the difference between dose conditions, dose-dependent differences in marijuana's cardiovascular effects and ratings of craving were observed, whereas subjective ratings of marijuana effects did not significantly vary as a function of dose.
活性大麻相对于非活性大麻会产生显著的主观、精神运动和生理影响，但证明这些影响与剂量有关一直很困难。这项在个体内进行的双盲研究旨在设计一种吸烟程序来获得大麻剂量反应函数。在四个门诊实验室会议中，每日吸食大麻的人（N = 17 名男性，1 名女性）从 3 支大麻香烟中吸食了 6 次 5 口烟（每口 2 口）。根据条件（0、2、4 或 6 个活跃烟嘴），从活性（≥5.5% Δ⁹-四氢大麻酚/THC）和非活性（0.0% THC）大麻中吸烟嘴的数量有所不同；总是在吸非活性烟嘴之前吸活性烟嘴。在吸食大麻前后以及设定的时间点评估主观、生理和表现效果。尽管有证据（一氧化碳呼气，吸烟后大麻香烟的重量）表明参与者吸入的每支活性大麻香烟比非活性香烟少，但活性大麻剂量依赖性地增加了心率并降低了大麻渴望。与非活性大麻相比，活性大麻增加了大麻“强度”、“高”、“喜欢”、“好效果”和“再吸”的主观评分，但这些效果与剂量无关。与非活性条件相比，活性大麻也会适度且非剂量依赖性地损害注意力、精神运动功能和记忆力。总之，尽管随着大麻强度的变化，吸入模式的变化可能会最小化剂量条件之间的差异，但观察到了大麻心血管作用和渴望评分的剂量依赖性差异，而大麻作用的主观评分并没有随着剂量的变化而显著变化。
