A combination of cetirizine and pseudoephedrine has therapeutic benefits when compared to single drug treatment in allergic rhinitis.
Antihistamines and nasal decongestants are well-established therapeutics in allergic rhinitis. However, no data are available which directly compare the effect size of the single substances with their combination in a single study including placebo (PLA) treatment.


OBJECTIVE
The aim of this study was to evaluate the effect of a combination of cetirizine (CET) and pseudoephedrine (PSE) and to compare it to treatment with CET or PSE alone and to PLA during grass pollen allergen challenge in an environmental challenge chamber (ECC).


METHODS
In a randomized, double-blind, placebo-controlled, four-way crossover study the effect of a combination of 10 mg CET with 120 mg PSE (CET + PSE) versus CET or PSE alone or PLA on symptoms, nasal flow, and nasal secretions was investigated in 49 patients with intermittent allergic rhinitis. Subjects underwent four 6-h pollen exposures in an ECC with administration of the drugs after 2 h.


RESULTS
The induction of nasal symptoms, nasal secretion and nasal obstruction (measured as nasal flow) during the first 2 h of pollen exposure was highly reproducible at the 4 consecutive exposures. The symptom of nasal obstruction was significantly reduced after treatment with CET + PSE compared to the treatment with CET or PSE alone or PLA (p < 0.0001). Furthermore, the combination treatment significantly reduced the total nasal symptom score (TNSS) and visual analogue scale score (VAS) compared to the single treatments or PLA. Nasal flow was significantly increased after treatment with CET + PSE and PSE and nasal secretions were significantly reduced by CET + PSE and CET without significant additional improvement of the combination therapy.


CONCLUSIONS
The combination treatment with CET and PSE is more effective than treatment with single substances in subjects with allergic rhinitis.
Badorrek
P
P
Fraunhofer Institute of Toxicology and Experimental Medicine, Hannover, Germany. philipp.badorrek@item.fraunhofer.de
Dick
M
M
Schauerte
A
A
Hecker
H
H
Murdoch
R
R
Luettig
B
B
Hohlfeld
J M
JM
Krug
N
N
D000328:Adult; D017332:Cetirizine / Q000008:administration & dosage / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004338:Drug Combinations; D004357:Drug Synergism; D005260:Female; D039563:Histamine H1 Antagonists, Non-Sedating / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D014663:Nasal Decongestants / Q000008:administration & dosage / Q000627:therapeutic use; D015508:Nasal Obstruction / Q000188:drug therapy / Q000209:etiology; D011058:Pollen / Q000276:immunology; D054199:Pseudoephedrine / Q000008:administration & dosage / Q000627:therapeutic use*; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy* / Q000276:immunology; D055815:Young Adult
D004338:Drug Combinations; D039563:Histamine H1 Antagonists, Non-Sedating; D014663:Nasal Decongestants; D054199:Pseudoephedrine; D017332:Cetirizine