Direct family caregivers of population-based adolescents with intellectual disabilities in Taiwan were surveyed regarding their perceptions of the use of prescribed medication and its relationship with health-related behaviors, medical care and preventive health utilization of people with intellectual disabilities. Cross-sectional data on 1419 adolescents 12-17 years of age was collected from the "2007 National Survey on Healthy Behaviors and Preventive Health Utilizations of People with Intellectual Disabilities in Taiwan." Multiple logistic regression models were used to examine risk profiles in relation to the use of prescribed medication and other relevant variables: participant characteristics, health-related behaviors, medical care and preventive health utilization. The results indicate that 47.1% of subjects were accompanied by other impairments, the morbidity prevalence was 16.5% and 23.8% of subjects were reported to have used prescribed medication regularly in the past 6 months. The main reasons for medication use were epilepsy (36.9%), psychiatric problems (24.2%) and gastrointestinal problems (6.3%). A large majority of caregivers reported that the subject's health status was excellent (15.4%), good (38%) or fair (38%), and only 6.5% were reported to be in bad health. Finally, data were analyzed using a logistic regression model to identify possible reasons for drug use. The following factors correlate with the regular use of prescribed medication by adolescents with intellectual disabilities: Down syndrome, possession of a Major Illness Card, a history of smoking, an additional impairment, reported health status, outpatient care and acceptance of other specific medical examinations. Our principal conclusion was that these data indicate a need for more education on a variety of issues, including predisposition, healthy behavior, medical care and preventive health utilization issues as they relate to prescribed medication use, and assessment of the long-term effects of drug use on people with intellectual disabilities. (Contains 6 tables.)