We explored the relationships between behavioral, socio-cultural, and psychological characteristics and the use of prescription medications obtained from non-medical sources among predominantly Spanish-speaking Latinos in the rural southeastern U.S. Respondent-driven sampling (RDS) was used to identify, recruit, and enroll immigrant Latinos to participate in an interviewer-administered assessment. A total of 164 respondents were interviewed in 2009. Average age was 34 years old, 64% of respondents were female, and nearly 85% reported being from Mexico. Unweighted and RDS-weighted prevalence estimates of any non-medical source of prescription medications were 22.6% and 15.1%, respectively. In multivariable modeling, respondents who perceived their documentation status as a barrier to health care and those with higher educational attainment were significantly more likely to report use of non-medical sources. Interventions are needed to increase knowledge of eligibility to sources of medical care and treatment and ensure culturally congruent services for immigrant communities in the U.S.