- Children administered the following drugs within one week (6days) or 4 weeks (27days) before the start of the observation period [within one week] • Anti-histamine drugs (oral, injection, and nasal drop) • Chemical mediator release inhibitors (mast cell stabilizer) • Th2 cytokine inhibitors (suplatast tosilate) • Leukotriene receptor antagonists • Thromboxane A2 receptor antagonists