Table 9. Grading system for local adverse events in sublingual immunotherapy (SLIT) according to the World Allergy Organisation (279).

Symptom/sign

Pruritus/swelling of mouth, tongue, or lip; throat irritation*, nausea, abdominal pain, vomiting, diarrhea, heartburn, or uvular edema

Grade 1: mild

Not troublesome and no symptomatic treatment required and no discontinuation of SLIT because of local side effects

Grade 2: moderate

Troublesome or requires symptomatic treatment and no discontinuation of SLIT because of local side effects

Grade 3: severe

Grade 2 and SLIT discontinued because of local side effects

Unknown severity

Treatment is discontinued, but there is no subjective, objective, or both description of severity from the patient/physician

Each local adverse event can be early (<30 min) or delayed. *, for example, itchy palate, burning or swelling of the throat.