A laboratory study of patients with chronic allergic rhinitis: Antihistamine effects on skilled performance

Cognitive Effects of Allergic Rhinitis and its Treatment

“…Diphenhydramine produced consistent impairment on performance tests measuring attention and response time when patients were asymptomatic. Few differences between diphenhydramine and placebo emerged when patients were symptomatic, leading the authors to conclude that ''[i]f a drug is most impairing in the absence of symptoms, experiments with healthy subjects may overestimate the impairment that will occur when it is used by patients experiencing symptoms'' [30].…”

“…In one study, 24 adults with skin-prick confirmation of allergic response were seen on four occasions, two each with and without AR symptoms [30]. During both the symptomatic and asymptomatic periods, each patient was treated twice in a mixed-order crossover design, once with diphenhydramine, 50 mg, and once with placebo.…”

Special Considerations in the Treatment of Seasonal Allergic Rhinitis in Adolescents: The Role of Antihistamine Therapy

“…26 The administration ofdiphenhydramine (50 mg) impaired performance on all tests except the visual backward masking test. This impairment was most pronounced when diphenhydramine was administered to patients at a time when they were free of symptoms.…”

Diphenhydramine and Dimenhydrinate Poisoning: an Evidence-Based Consensus Guideline for Out-of-Hospital Management

“…There were, however, nine level 1b studies (individual randomized clinical trials) that were reviewed in which therapeutic doses (ranging from 37.5 to 75 mg) of diphenhydramine were administered to generally healthy volunteers of varying ages (37)(38)(39)(40)(41)(42)(43)(44)(45). No serious toxicity was noted in these studies.…”