TABLE VIII.E.4.a-2.

Aggregate grades of evidence: medications that affect allergy skin testing

H1 antihistamines	Aggregate Grade of Evidence: A (Level 1b: 2 studies, Level 2b: 3 studies) • Should be discontinued 2-7 days prior to testing.
H2 antihistamines	Aggregate Grade of Evidence: B (Level 1b: 2 studies) • Ranitidine suppresses skin whealing response, may result in false negatives.
Topical antihistamines (nasal, ocular)	Aggregate Grade of Evidence: Unable to determine from one Level 1b study. • Should be discontinued 2 days prior to testing.
Anti-IgE (omalizumab)	Aggregate Grade of Evidence: A (Level 1b: 2 studies) • Results in negative allergy skin test results.
Leukotriene receptor antagonists	Aggregate Grade of Evidence: A (Level 1b: 2 studies, Level 2b: 1 study) • May be continued during testing.
Tricyclic antidepressants	Aggregate Grade of Evidence: Unable to determine from one Level 2b study. • Agents with antihistaminic properties suppress allergy skin test responses.
Topical (cutaneous) corticosteroids	Aggregate Grade of Evidence: A (Level 1b: 2 studies, Level 2b: one study) • Skin tests should not be placed at sites of chronic topical steroid treatment.
Systemic corticosteroids	Aggregate Grade of Evidence: C (No effect – Level 1b: 1 study, Level 2b: 1 study; Suppression – Level 3b: 1 study, Level 4: 1 study) • Systemic corticosteroid treatment does not significantly impair skin test responses.
Selective serotonin reuptake inhibitors (SSRIs)	Aggregate Grade of Evidence: B (Level 2b: 1 study, Level 4: 1 study) • Does not suppress allergy skin test response.
Benzodiazepines	Aggregate Grade of Evidence: C (Level 4: 1 study, Level 5: 1 case report) • May suppress skin test responses.
Topical calcineurin inhibitors (ie. tacrolimus, picrolimus)	Aggregate Grade of Evidence: D (Level 1b: 1 study, Level 2b: 1 study – results conflicting) • Conflicting results regarding skin test suppression.