Background. - Substance use disorder (SUD) is related to the interplay of various factors. The primary objective of this study was to assess the variation in substance use (SU) among a set of Lebanese people undergoing treatment for SUD during the Lebanese economic crisis, COVID-19 pandemic, and Beirut Blast. Methods. - A cross-sectional study including Lebanese adults previously diagnosed with and being treated for SUD at the Skoun center was conducted. Data collection was done using a paper-based Arabic questionnaire tackling the economic crisis, the Covid-19 pandemic, and the Beirut Blast, as well as the following scores: APGAR, PHQ-9, GAD-7 and PCL-6. Data were analyzed using SPSS version 25.0 with P value < 0.05 considered significant. A bivariate analysis was conducted to study the association between the use of substances and study variables and scores. Results. - The sample included 126 men and 10 women. Most participants had a stable consumption of illicit drugs (58.8%), alcohol (76.5%), prescription drugs (70.6%) and non-prescription drugs (89%). Additionally, most participants had concomitant mild or moderate depression (55.1%), mild or moderate anxiety (50.7%), and PTSD (61.8%). Factors found to significantly increase SU were economic distress, change in employment status, and decrease in working hours. PTSD was also identified as a risk factor for increased illicit drug and alcohol use. Furthermore, severe anxiety was found to be a risk factor for increased alcohol consumption. Conclusion. - Most participants were able to maintain a stable pattern of SU despite the quadruple crisis in Lebanon highlighting the important role played by Lebanese Non-Governmental Organizations (NGOs) and efforts employed to control SUD.