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What is Which of the follwoing statements about theophylline is TRUE? and explain in detail?
(Ref: KDT 6/e p221) Theophylline has a narrow therapeutic index. Its use has been declined due to narrow safety margin. It inhibits the enzyme phosphodiesterase and thus decreases the metaboism of cAMP. It does not increase the formation of cAMP. Smoking is a powerful enzyme inducer. Dose of theophylline should be increased in smokers. Children metabolize theophylline faster than adults whereas elderly metabolize it slowly. Therefore, half life of theophylline is shoer in children as compared to adults.