An Ecological Examination of Indica Versus Sativa and Primary Terpenes on the Subjective Effects of Smoked Cannabis: A Preliminary Investigation

Background: The legal cannabis landscape has greatly outpaced scientific knowledge. Many popular cannabis claims, such as cultivar (colloquially referred to as strain) classification and terpene content producing different subjective effects, are unsubstantiated. This study examined, for the first time, whether cultivar classification (sativa/indica) and terpene content (caryophyllene, limonene, myrcene, pinene, and terpinolene) were associated with subjective cannabis effects (i.e., pain levels, low-arousal [“indica-like”] effects, high-arousal [“sativa-like”] effects, and negative effects).

‘Methods: Regular cannabis users (n=101) took part in a 2-week long ecological momentary assessment study in which they responded to questions about their cannabis use, stated their preference for sativa versus indica, and reported their in-the-moment subjective effects within 30 min of smoking cannabis. Cultivars were coded for sativa versus indica classification and primary terpene content using Leafly, a popular search engine. Linear mixed-effect models then examined subjective response by sativa/indica and primary terpene. Covariates included demographics (age, sex, race, income), cannabis use (medical use, cannabis use frequency, stated preference for sativa/indica, global expected cannabis effects), morning pain ratings, and specific smoked cannabis occasions (hour of day, minutes since use, context, number of hits, and tetrahydrocannabinol).

Results: The majority of participants (78.3%) had a preference for either sativa or indica and reported reasons for their preference that aligned with industry claims. After controlling for covariates, findings revealed that cultivars classified as indica dominant were associated with greater low-arousal (e.g., sluggish, slow) effects relative to the unweighted mean of all cannabis cultivars (b = 0.44, SE=0.16, p=0.01). Cultivars with primary caryophyllene were associated with greater pain ratings (b = 0.53, SE=0.24, p=0.03) and negative effects (b = 0.22, SE=0.08, p=0.01) relative to the mean of all other terpene types. Cultivars with primary pinene were associated with less negative effects (b = -0.35, SE=0.18, p=0.04).

Conclusions: Cultivars classified as indica dominant were associated with greater low-arousal effects in models that accounted for both within- and between-person variation, despite the scientific challenges distinguishing between sativa and indica. Preliminary findings also suggest terpenes may play a role in subjective effects. These results emphasize the need for further research, particularly controlled lab studies.