Oral challenges to detect aspirin and sulfite sensitivity in asthma.

Oral challenge with aspirin or potential cross-reacting substances (including other nonsteroidal anti-inflammatory drugs [NSAIDs] or food and drug additives) is an effective method for establishing the presence of sensitivity to these substances in asthmatic subjects. Sulfite challenges can be performed in a similar manner. However, many of these subjects have concomitant active irritable airways that could make testing both inaccurate and potentially dangerous. This paper contains strategies for dealing with these problems as well as other important details in conducting oral challenges in asthmatic subjects in a manner which will lead to valid data and conclusions.