BACKGROUND: The COVID-19 pandemic and its lockdown measures disrupted daily life globally, potentially impacting substance use and mental health. However, the effects in Morocco, shaped by cultural and social factors, remain underexplored. This study aimed to assess the impact of the COVID-19 lockdown on psychoactive substance use and mental health in Morocco, while identifying key socio-demographic determinants of these changes.

METHODS: A cross-sectional online survey was conducted in April 2020, with 1,001 participants who had used at least one psychoactive substance in the past year. Data on substance use changes, socio-demographic characteristics, and emotional states were collected. Chi-square and McNemar's tests were used for statistical analysis.

RESULTS: The results indicated a significant reduction in the consumption of tobacco, alcohol, cannabis, and other substances during the lockdown (p < 0.001). The main reasons for this decrease were health concerns (37.6%) and limited consumption opportunities (25.9%). Younger individuals (18–30 years), students, and those with lower incomes were more likely to reduce their use (p < 0.05). Furthermore, 71.3% of participants reported worsened emotional states, with worry (66.6%) and loneliness (52%) being the most common.

CONCLUSION: The COVID-19 lockdown led to a significant reduction in substance use in Morocco, mainly due to restricted access and lifestyle changes. However, it was also associated with worsened mental health, highlighting the need for culturally appropriate mental health support and harm-reduction strategies during crises.

KEYWORDS: COVID-19, psychoactive substances, mental health, lockdown, Morocco, substance use patterns.