SUMMARY
Objective: This work describes the medicinal plants and/or herbal medicines usage by the population assisted by Brazilian Public Health System (SUS), and their prescription by health professionals in the Brazilian Northeast. Methods: Questionnaires were applied for public health system users; pharmacists who work at compounding pharmacies; physicians and nurses. Data were submitted to descriptive statistical analysis. Results: The sociodemographic profile was individuals between 40 and 59 yearsold, majority of females, low family income, and low schooling levels. A great number of individuals (89.3%) used plant products, without prescription and based on traditional knowledge. There was a common trend regarding a lack of knowledge of plant toxicity potential. Regarding health professionals, 90% stated having knowledge about medicinal plants and/or herbal medicines, and 80% believe that its effect is important. Conclusion: The study reveals the major usage of herbal medicines and/or medicinal plants by familiar low income and low schooling level without prescription from a physician. These factors may cause a risk/benefit imbalance where could have a reduction in therapy efficacy and high toxicity potential of the drugs. This reinforces the need of pharmacosurveillance toward usage of medicinal plants and herbal medicines in the public health system.