Ecstasy is commonly used on weekends and linked to post-use mood declines. Laboratory studies with pure MDMA rarely detect residual effects, whereas naturalistic studies more often report mood reductions. The timing and contextual drivers of these effects remain unclear. Data from seventeen ecstasy users (10 male, 7 female; 19–38 years) were drawn from a previously conducted study and analyzed for temporal mood changes not identified in the original report. Participants completed observation weeks following both ecstasy-use and nonuse weekends. Daily diaries assessed mood (0–10), other affective states, drug use, and sleep-related measures. Weekly BDI-II and BAI scores were collected. A significant Weekend Ecstasy X Day interaction was present ( F (3,48) = 3.41, p = 0.037), driven by lower Monday mood after ecstasy-use weekends ( t (16) = 2.36, p = 0.031). This effect remained after adjusting for other drug use (β = –1.44, p = 0.018), but was attenuated when hours in bed were included (β = –0.82, p = 0.17), which independently predicted lower mood (β = –0.29, p = 0.019). Mediation analyses indicated that increased time in bed largely accounted for the Monday decrease. No differences were found for the BDI-II and BAI. Exploratory analyses showed reduced Thursday physical tension/agitation after ecstasy-use weekends ( p = 0.008). Residual mood effects appear Monday-specific and are attenuated when inactivity is considered, suggesting recovery-related behavior—not MDMA alone—may underlie post-use mood declines. Because increased time in bed may both reflect and influence low mood, directionality cannot be determined. • Monday mood dips after ecstasy-use weekends in daily diary reports. • Inactivity (more hours in bed) largely accounts for Monday mood decline. • Ecstasy weekends do not elevate Wednesday clinical depressive or anxiety symptoms. • Thursday shows reduced physical tension/agitation, especially among female users. • Behavioral factors may better explain mood effects than ecstasy alone.
Medina-Kirchner et al. (Sun,) studied this question.