Table 1.

Efficacy of drugs to treat AR and recommendation level, according to Aggregate Grade of Evidence (AGE) from International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis [12]

Type of drug and pharmaceutical preparations	AGE	Number of listed studies	Recommendation level
Oral H1 antihistamines	A	Level 1a: 21 studies	Strong recommendation
Intranasal antihistamines	A	Level 1b: 43 studies Level 2b: 1 study	Recommendation
Intranasal corticosteroids (INCS)	A	Level 1a: 15 studies Level 1b: 33 studies Level 2a: 3 studies Level 2b: 1 study Level 5: 1 study	Strong recommendation
Combination: INCS and intranasal antihistamine	A	Level 1b: 9 studies Level 2b: 1 study Level 2c: 2 studies	Strong recommendation
Oral corticosteroids	B	Level 1b: 5 studies Level 2b: 1 study Level 4: 3 studies	Recommendation against
Injectable corticosteroids	B	Level 1b: 3 studies Level 2b: 3 studies Level 4: 7 studies	Recommendation against
Oral decongestants	B	Level 1a: 2 studies Level 1b: 3 studies Level 3b: 2 studies Level 4: 2 studies	Option for pseudoephedrine for short term treatment Recommend against phenlylephrine
Intranasal decongestants	B	Level 1b: 3 studies Level 2b: 1 study	Option
Leukotriene receptor antagonists	A	Level 1a: 6 studies Level 1b: 17 studies Level 2a: 2 studies Level 2b: 3 studies Level 4: 3 studies	Recommendation against
Cromolyn (DSCG)	A	Level 1b: 13 studies Level 2b: 9 studies	Option
Intranasal anticholinergics (IPB)	B	Level 1b: 9 studies Level 2b: 5 studies	Option
Biologics (omalizumab)	A	Level 1a: 1 study Level 1b: 5 studies	No indication

Aggregate grade of evidence (AGE)
Grade	Research quality
A	Well-designed RCTs
B	RCTs with minor limitations; overwhelming consistent evidence from observational studies
C	Observational studies (case control and cohort design)
D	Expert opinion; Case reports; Reasoning from first principles