Serum corticosterone concentrations were evaluated in 40 adult Hispaniolan Amazon parrots (Amazona ventralis) after manual restraint and anesthesia and before and after skin testing. Twenty-four to 72 hours before the skin testing, blood samples were collected immediately after capture from manually restrained birds. On 2 separate days, half of the parrots in the study group (20 birds each) were anesthetized with isoflurane, and blood samples were taken immediately before and at 2.5, 7.5, and 17 minutes after skin testing. Serum samples were assayed by radioimmunoassay for corticosterone concentration. Although baseline corticosterone concentrations plotted against time varied in both anesthetized and manually restrained parrots, a downward trend was seen at 1400 hours (anesthetized birds) and at 1300 hours (manually restrained birds). The mean baseline concentration (±SEM) of corticosterone measured in birds that were manually restrained was significantly higher (33.7 ± 2.83 ng/ml) than that in anesthetized birds (19.8 ± 1.97 ng/ml). Mean corticosterone concentrations (±SEM) in anesthetized birds increased progressively after skin testing, from 19.8 ± 2.02 ng/ml before skin testing to 52.7 ± 2.63 ng/ml at 2.5 minutes, 63.1 ± 2.3 ng/ml at 7.5 minutes, and 74.5 ± 2.79 ng/ml at 17.0 minutes after skin testing. In birds, this increase in serum corticosterone concentration may account for the weak wheal formation observed during skin testing and emphasizes the need to read skin test results within a few minutes after intradermal injection.