Objective The primary objective of the study was to evaluate the effects of communication style on risk perception of medication side effects. Secondary objective was to evaluate the effect of risk perception and communication style on intention to adhere to medications. Methods The study was an experimental cross-sectional and factorial design. Participants were exposed to information on four medications and each associated with a side effect. The description of the side effect was presented in one of eight combinations from a 2 (communication style: verbal or verbal combined with numeric) X 2 (frequency: low or high) X 2 (severity: mild or severe), factorial design. The three factors acted as independent variables. Dependent variables of perceptions of risk of experiencing side effects and intention to adhere to medication was recorded for each of the four side effects on a Visual Analogue Scale ranging from 0 to 100. Demographic information on age, gender, education, profession (healthcare/non-healthcare) and race was also recorded. Data was coded and analyzed using SAS Version 9.3 at an apriori significance level of 0.05. Multivariate analysis or covariance was performed to test the effects of communication style severity and frequency on risk perception and intention to adhere. Separate univariate analyses tests were also performed to test the effects of the three dependent variables on the two independent variables. Results A total of 196 completed surveys were obtained giving a response rate of 81.6%. MANCOVA results indicated that communication style did not show any significant main effects but showed significant effects in interaction with frequency [F (3,772) = 10.43; p<0.001]. Significant effects were also observed for frequency of side effects [F (3,772) = 169.93; p<0.001], severity of side effects [F (3,772) = 98.33; p<0.001] as well as their interaction [F (3,772) = 44.30; p<0.001]. Separate univariate ANCOVAs also showed same effects for risk perception. Frequency of side effects showed the maximum effects from all the three factors. Although overall interaction of communication style, frequency and severity was not significant, least square means for risk perception showed that effects of communication style were significant only for certain combinations of severity of frequency. It was observed that for low frequency severe side effects, perceptions of risk decreased when combination of verbal and numeric descriptions were used to communicate the side effect risk as compared to only verbal communication style [Mean difference = 11.24, p=0.0008]. For high frequency mild side effects, perceptions of risk increased when combined communication style was used as compared to only verbal communication style [Mean difference = 7.80, p=0.0203]. Risk perception was found to be negatively associated with intention to adhere [β=0.61, p<0.0001]. There were no effects of communication style on intention to adhere. However intention to adhere was observed to decrease with increase in frequency and severity of side effects. Conclusion Perceptions of risk of experiencing side effects and intention to adhere are primarily affected by the frequency and severity of side effects. Communication style plays a role in conjunction with side effect frequency in affecting perceptions of risk. Low frequency side effects are often associated with overestimation of risk when only verbal descriptions are used and hence should be carefully communicated. Overall, use of numeric descriptors along with verbal descriptors lead to better understanding of side effect frequency.