OBJECTIVE: The objective of this review was to identify the effectiveness of topical medications on radial artery spasm (RAS) in patients undergoing transradial percutaneous coronary procedures. INTRODUCTION: Percutaneous coronary procedures were traditionally carried out via the femoral artery; however, over the last 20 years there has been a global increase in the number of proceduralists carrying out percutaneous coronary procedures via the transradial approach. Radial artery spasm remains an issue for the transradial approach, potentially leading to procedural failure. Topical medications have been suggested to reduce the occurrence of RAS during transradial percutaneous coronary procedures. INCLUSION CRITERIA: This review considered papers that included participants aged 18 years and over undergoing non-emergency transradial percutaneous coronary procedures. This review considered papers on the utilization of topical medications prior to commencing the transradial approach for percutaneous coronary procedures to reduce RAS. Topical medications were compared to other medications. The primary outcome was the incidence of RAS as assessed by angiography or ultrasound or resistance felt by the operator while manipulating the catheter. Other outcomes of interest included change in radial artery diameter, measured by angiography or ultrasound, change in radial artery patency and side effects of medications administered. Randomized and quasi-randomized controlled trials were considered. METHODS: A three-step search strategy was utilized in this review. A search of various databases was carried out followed by a search for unpublished literature between 1989 to January 2017. Only papers published in English were included in the review. Papers selected for retrieval were assessed by two independent reviewers for methodological validity prior to inclusion in the review using standardized critical appraisal instrument from the Joanna Briggs Institute (JBI). There was no need for a third reviewer. Quantitative data was extracted from papers included in the review using the JBI data extraction instrument and entered in to RevMan5 (Copenhagen: The Nordic Cochrane Centre, Cochrane). All results were subject to double data entry. Effect sizes were expressed as odds ratio (for categorical data) and weighted mean differences (for continuous data) and their 95% confidence intervals were calculated for analysis. RESULTS: Only three studies involving 697 participants met the inclusion criteria. There was a statistically significant reduction in the incidence of RAS in patients treated with a eutectic mixture of local anesthetics compared to subcutaneous lidocaine (OR 0.26; 95%CI 0.07,0.96). However there were no significant differences in RAS in studies that compared eutectic mixture of local anesthetics and placebo or a combinations of lidocaine with nitroglycerine compared to placebo. CONCLUSIONS: It is difficult to draw a valid conclusion, given the low number of studies, small sample sizes and heterogeneity between the studies.