Background: Alcohol use disorder (AUD) is disabling yet neglected and frequently leftrnuntreated in low- and middle-income countries (LMICs). To increase the treatment rate, AUDrnservices need to be integrated into primary health care (PHC) units as people with the disorderrnoften make contact with PHC due to physical health consequences of AUD. rnObjectives: 1) To determine the magnitude of AUD and associated disability, co-morbidrndepression, suicide, internalized stigma and help seeking behavior in Sodo district, Gurage Zone,rnSouth-Central Ethiopia. 2) To assess the impact of a brief intervention delivered at PHC onrnalcohol use after 12 months. 3) To explore the perspectives and experiences of people withrnAUD, caregivers and service providers about the brief intervention delivered at PHC in Sodorndistrict. rnMethods: The study was nested within the PRogrammme for Improving Mental health carErn(PRIME). Mixed quantitative and qualitative methods were used: 1) Using a cross-sectionalrnhouse-to-house community survey of 1500 adults (aged 18 years and above) living in Sodorndistrict. The prevalence of AUD help seeking behavior, barriers to care, disability, co-morbidrndepression, internalized stigma and suicidality were determined. AUD was assessed using arnculturally adapted version of the Alcohol Use Disorders Identification Test (AUDIT), A Poissonrnworking model with robust variance was used to determine prevalence ratios. 2) A pilot beforeand-afterrnrnstudy was carried out among 49 people attending PHC facilities who had probablernalcohol use disorder. Participants received an evidence-based single session brief intervention forrnAUD which was delivered by trained PHC workers. Follow-up assessment was conducted at 3rnand 12 months. This included evaluation of AUD severity, functioning using World healthrnorganization disability assessment schedule (WHODAS 2) Score), consequences of drinkingrnusing Short Inventory of Problems revised version 2 (SIP-2R) and depression using the patientrnhealth questionnaire (PHQ-9). A mixed-effect linear model was used to assess the impact of thernintervention at 3 and 12 months. 3) A nested qualitative study was conducted to explorernperceptions and experience of service users, caregivers and service providers on thernacceptability, impact and implementation of the intervention. Twenty-six in-depth interviews rnwere conducted with 14 people with alcohol use disorder, four caregivers and eight healthrnprofessionals who were providing the intervention. Framework analysis was used for analysis. rnResults: The prevalence of alcohol use disorder was 13.9% (25.8% in men and 2.4% in women).rnAlcohol used disorder was more prevalent among men (adjusted prevalence ratio (aPR) 7.7, 95%rnconfidence interval (CI): 4.4, 13.1; farmers aPR 3.9, 95% CI: 1.0, 14.8), traders (aPR 6.0, 95%rnCI: 1.5, 23.9) and daily laborers (aPR 6.3, 95% CI: 1.5, 26.1) compared to housewives. A oneyearrnrnincrease in age was associated with a 1% increase in the prevalence of AUD (aPR 1.01,rn95% CI: 1.00, 1.02). As the number of stressful events, depressive symptom score and disabilityrnscore increase by one, the prevalence of AUD increased by 27% (aPR 1.2, 95% CI: (1.1, 1.3),rn3.0 % (aPR 1.03, CI: 1.01, 1.03) and 2.0% (aPR 1.02, 95% CI: 1.01, 1.04), respectively. Havingrnsuicidal thoughts was also associated with AUD (aPR = 1.5; 95%CI: 1.1, 2.1). Of participantsrnwith an AUDIT score â‰¥16 (indicating harmful drinking), only 13% (n=6) sought help for alcoholrnproblems, and 70.0% reported high internalized stigma. Major barriers to seeking help were:rnwanting to handle the problem on their own, believing that it would get better by itself, beingrnunsure about where to go, not bothered by the problem, financial barriers, including beingrnconcerned about the cost of professional help, concerned about what people might think, andrnaccess. Forty-nine people with AUD received the brief intervention, and 92 % completed thernassessments. Following the brief intervention, there was a statistically significant reduction inrnAUD severity, consequences of drinking and depressive symptoms. The adjusted meanrndifference (AMD) in AUDIT score at 3-months was -2.66 (95% CI -5.21, -0.11) and at 12rnmonths was -4.15 (95% CI -6.76, -1.54). For SIP-2R score, AMD for AUDIT score was -2.52rn(95% CI -4.86, -0.18) at 3-months and -3.00 (95% CI -5.87, -0.14) at 12-months. For PHQ-9rnscore AMD was -2.06 (95% CI -3.35, -0.77) at 3-months and -2.03 (95% CI -3.35, -0.72) at 12months.rnrnAlthough positive effects of the intervention on functioning were not seen in thernquantitative analysis, the qualitative study strongly supported the impact of the intervention onrnimproving functioning. People with AUD and caregivers reported improved work capacity,rnincreasing earnings, less money wasted and, consequently, being able to better provide for theirrnfamily. The brief alcohol intervention was accepted by most service users. Service providersrnreported low acceptability of their advice by participants, participantsâ€™ lack of openness to talkrnabout alcohol, and shortage of space as barriers for implementation. Primary health care workersrnrecommended further training, raising awareness of the community about alcohol use disorder, and working with the community and health extension workers. They also requested a strongerrnadministrative support system for improving management of alcohol use disorder. rnConclusions: Although alcohol use disorder was a common problem in the study setting, thernunmet need for treatment was substantial. A pilot integration of a single session briefrnintervention in PHC had a positive impact on the severity of AUD, consequences of drinking,rnand depressive symptoms over a period of 12 months. The intervention was also feasible,rnacceptable and perceived to bring benefits. However, there is a need to address such issues asrnlow community awareness about AUD, stigma, inadequate skills of PHC workers andrnengagement of the community in order to increase help-seeking behavior, and enhancernacceptability and the impact of intervention in PHC settings. With more frequent supervision,rnnon-specialized workers at the PHC level have the potential to contribute to the reduction of thernburden of AUD through early screening, brief intervention, and referring people with severernAUD for specialist treatment.