Background: Patient misuse of prescriptions is a factor contributing to medication error statistics involving patient deaths and injuries. Caregiver medication administration errors as well as patient and/or caregiver misunderstanding of medication instructions occur frequently in the home setting. The information is often complex and requires that patients/caregivers have the capacity to process and understand health information as well as possess adequate numeracy-related skills. Simplifying the information into a structured sequence of instructions with supporting visuals might be a potential solution to help patients to understand quantitative information. Methods: This study compares adult understanding of medical prescription instructions using sequential pictorial instructions (SPIs) vs. written instructions (WRIs). A sample of 359 parents (18 to 82 years old) of pediatric patients participated in an assessment comparing SPIs (n=195, 54.3%) vs. WRIs (n=164, 45.7%). The medical instruction assessment included questions regarding prescriptions, appointments/non-critical instructions, and emergency situations. Results: Total and subgroup scores for questions regarding prescriptions and emergency situations were significantly higher among participants responding to the SPIs when compared to the written scores. Discussion: Initial findings indicate that SPIs might be a valuable addition to existing strategies to increase understanding of medical instructions.