All of the following drugs can precipitate acute attack of asthma except

Refer KDT 6/e p217 COX inhibitors like aspirin, indomethacin, naproxen, and phenyl butazone etc inhibit the formulation of PGs from arachidonic acid This results in diversion of metabolism of arachidonic acid to produce LTs Large excess of LTs are therefore produced with the use of NSAIDS These drugs therefore Cam result in precipitation of acute attack of asthma