title: Nasal methacholine provocation and ipratropium therapy of perennial rhinitis.
mesh_terms: D000281:Administration, Intranasal; D001286:Atropine Derivatives / Q000627:therapeutic use*; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D004341:Drug Evaluation; D006801:Humans; D009241:Ipratropium / Q000008:administration & dosage / Q000627:therapeutic use*; D008688:Methacholine Compounds / Q000008:administration & dosage / Q000037:antagonists & inhibitors; D009297:Nasal Mucosa / Q000378:metabolism; D006255:Rhinitis, Allergic, Seasonal / Q000175:diagnosis* / Q000188:drug therapy; D012636:Secretory Rate / Q000187:drug effects
chemical_list: D001286:Atropine Derivatives; D008688:Methacholine Compounds; D009241:Ipratropium