BACKGROUND: The prevalence of the photic sneeze response (PSR) as well as other characteristics have been studied in selected populations. However, the PSR has not been investigated in a general eye care patient population. This study was performed in an attempt to characterize the epidemiologic, descriptive, and demographic aspects of the photic sneeze response among patients attending for primary eye care. METHODS: A questionnaire on demographics, risk factors, and triggering stimuli was distributed to 500 consecutive patients presenting for a general eye examination at an academic health center optometry clinic. RESULTS: Three hundred and sixty-seven of 500 questionnaires were returned (73.4%). Among this sample 33% were self-recognized photic sneezers with the majority being females (67%) and Caucasian (94.3%). Statistically significant correlations were found between the presence of photic sneezing and the presence of a deviated nasal septum and a non-significant association was found with tobacco use. Uniform frequency of sneezing does not occur in response to light stimulus; only 12.3% of sneezers responded consistently to sunlight exposure. The majority of sneezers (90.7%) responded with three or fewer sneezes. The interval between successive sneezes was fewer than 19 seconds in 85% of respondents. Fewer than 27% of respondents were able to recall a parent who exhibited a sneeze response. CONCLUSIONS: The PSR is not an uncommon phenomenon. Systemic associations with the PSR are as diverse as deviated nasal septum and tobacco use. Results suggest that there may be a threshold level of light or frequency of light exposure which produces the response and that more patients may acquire the response than inherit it.