Seventy-three patients at The Mount Sinai Hospital Emergency Room were investigated to determine the prevalence of atopy in asthma in a predominantly black and Hispanic inner-city population. Serum IgE levels and radioallergosorbent tests (RASTs) to eight common inhalant allergens were measured in both the asthmatic group and a nonasthmatic emergency-room control group. The mean total IgE level for the asthma group was 263.8 IU/mL compared to 63.8 IU/mL in the control group (p = 0.032), and 60% of the asthmatics had IgE levels in the atopic range (> 100 IU/mL). Increases in IgE were associated with age under 50 years but did not reach statistical significance. Cockroach, dust mite, cat, and dog were the most common RASTs in the asthmatic group; there were no positive RASTs in the control group. There was a correlation (p = 0.04) between age (less than 50 years) and increased numbers of positive RASTs. These results are similar to those of other studies that have associated atopy with asthma in rural and suburban populations. These data demonstrate that atopy is common in the asthmatic patients seen in The Mount Sinai Hospital Emergency Room and strongly suggest that management of atopic factors should become routine in the care of adult asthmatic patients.