Effect of topical levocabastine on nasal response to allergen challenge and nasal hyperreactivity in perennial rhinitis.
BACKGROUND
It has been demonstrated that some oral antihistamines reduce nasal nonspecific reactivity and that topical levocabastine reduces cellular influx after nasal allergen challenge. This suggests that antihistamines possess other properties besides classical H1-receptor antagonism.


OBJECTIVE
To evaluate the effect of 1 week's treatment with topical levocabastine on the nasal clinical response, inflammatory mediators, and nasal hyperreactivity.


METHODS
In a double-blind, placebo-controlled, 2-period, 2-treatment, crossover study, 21 rhinitic patients allergic to house dust mite participated. After each treatment period patients were challenged with house dust mite extract. Symptom scores and nasal lavages were collected for nine and one-half hours after challenge. Allergen-induced nasal hyperreactivity was determined by nasal methacholine challenge 24 hours after allergen challenge. A nasal histamine challenge was performed as well.


RESULTS
Patients showed only an immediate nasal response. Levocabastine significantly reduced the symptom score after 100 (P = .0063), 1000 (P = .0035), and 10,000 biological units (BU)/mL (P = .0013) of house dust mite extract. Albumin influx and tryptase release were not significantly reduced by levocabastine. No release of histamine and eosinophil cationic protein was seen. Levocabastine did not reduce nasal response to methacholine. Active treatment significantly reduced histamine-induced nasal secretion (P = .0009) and the number of sneezes (P = .0001).


CONCLUSIONS
A significant effect of levocabastine was shown on the immediate clinical response to house dust mite and to histamine challenge only. Our findings suggest that levocabastine is an effective H1-receptor antagonist without anti-inflammatory properties.
de Graaf-in 't Veld
T
T
Department of Allergology, University Hospital Rotterdam-Dijkzigt, The Netherlands.
Garrelds
I M
IM
van Toorenenbergen
A W
AW
Mulder
P G
PG
Gerth van Wijk
R
R
Boegheim
J P
JP
D000287:Administration, Topical; D000328:Adult; D000418:Albumins / Q000378:metabolism; D000485:Allergens / Q000009:adverse effects; D000818:Animals; D039741:Antigens, Dermatophagoides; D053818:Chymases; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006023:Glycoproteins / Q000009:adverse effects; D006632:Histamine / Q000494:pharmacology; D006634:Histamine H1 Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D008297:Male; D016210:Methacholine Chloride / Q000008:administration & dosage; D008875:Middle Aged; D008925:Mites; D017817:Nasal Lavage Fluid / Q000737:chemistry / Q000166:cytology; D009297:Nasal Mucosa / Q000187:drug effects*; D009299:Nasal Provocation Tests; D010880:Piperidines / Q000494:pharmacology* / Q000627:therapeutic use; D012221:Rhinitis, Allergic, Perennial / Q000188:drug therapy* / Q000209:etiology; D012697:Serine Endopeptidases / Q000378:metabolism; D053802:Tryptases
D000418:Albumins; D000485:Allergens; D039741:Antigens, Dermatophagoides; D006023:Glycoproteins; D006634:Histamine H1 Antagonists; D010880:Piperidines; D016210:Methacholine Chloride; D006632:Histamine; D012697:Serine Endopeptidases; C083294:chymase 2; D053818:Chymases; D053802:Tryptases; C047340:levocabastine