Reuse of needles and syringes after home injection of medications and vitamins may be a risk for transmission of HIV. An exploratory study was done to determine (1) how commonly injectable medications were used in the home; (2) whether needles and syringes were reused; and (3) common practices for cleaning needles and syringes. A survey was conducted of low income Latina women (n = 216) who were attending a Public Health Foundation nutrition programme for women, infants and children (WIC) in Los Angeles. To clarify and expand on the survey findings, focus group interviews were done with an additional 55 women attending WIC. Quantitative data were analysed using descriptive and comparative statistics. Qualitative data were subjected to content analysis. The use of injectable medications purchased in Mexico was fairly common (43.5%); reuse of disposable needles and syringes (48%) and sharing (36%) among injectors were also common. Methods of cleaning needles and syringes were inadequate to CDC recommended guidelines. Injectors and non-injectors differed significantly in ethnicity, religion, and marital status. The only significant predictor of medication injection was educational level. Analysis of qualitative data revealed the reasons that Latina subjects were injecting medication; how they were transporting medicines from Mexico; and how they were cleaning their equipment. The practical implications for health education and prevention programmes should include an awareness that home use and reuse of needles for injection of medications may be common in some social groups and that knowledge of the potential dangers in reuse and sharing of needles may not extend to home medication injection.