Comparison of actions of disodium cromoglycate and ketotifen on exercise-induced bronchoconstriction in childhood asthma.

Abstract

Comparison of actions of disodium cromoglycate and ketotifen on exercise-induced bronchoconstriction in childhood asthma Ketotifen (Zaditen), a benzocycloheptathiophene derivative, is a new oral agent for treating asthma, with action similar in some respects to that of sodium cromoglycate.It is well established that sodium cromoglycate protects against antigen challenge by inhibiting the release of chemical mediators from mast cells.It also inhibits exercise- induced bronchoconstriction and has bronchodilator properties.' Ketotifen has a similar capacity to inhibit the release of chemical mediators from mast cells.2Its clinical effectiveness is still uncertain.3Patients, methods, and resultsTwenty-three children with a clinical history of asthma and a value on the Jones lability index greater than 20 % were examined.The decrease in peak expiratory flow rate (PEFR) below the resting value was examined and remeasured on another day after the child had been given 20 mg sodium cromoglycate solution via a Wright nebuliser and mains-driven compressor (Aerosol Products Ltd) 15 minutes before running.On a third day the test was repeated with 20 mg sodium cromoglycate powder given 15 minutes before exercise.It was repeated on a fourth day after the patient had received three days' treatment with ketotifen (1 mg twice a day by mouth).The last dose was given two hours before the test.The percentage fall index ((PEFR at rest-PEFR after exercise/PEFR at rest) x 100) was measured in each case. CommentMany patients with rheumatological disorders are treated with ibuprofen.From this case apparently a depressed level of conscious- ness and hypotension may result soon after ingestion of more than the maximum dose.Side effects when taking the normal dose include headache, amblyopia, and lightheadedness but there is no record of depressed consciousness.The findings of Adams et all in animals on 20 August