Which drug can exacerbate asthma secondary to irreversible nonselective inhibition of cyclooxygenase pathway?

Ans. is 'a' i.e., Aspirin * Aspirin inhibits COX irreversibly by acetylating one of its serine residues; return of COX activity depends on synthesis of fresh enzyme (not on the pharmacokinetic clearance of the drug). On the other hand, Other NSAIDs are competitive and reversible inhibitors of COX, return of activity depends on their dissociation from the enzyme which in turn is governed by the pharmakokinetic clearance from the body.Aspirin Induced Asthma* The disorder is thought to be caused by an anomaly in the arachidonic acid metabolizing cascade which leads to increased production of proinflammatory cysteinyl leukotrienes, a series of chemicals involved in the body's inflammatory response.* When medications like NSAIDs or aspirin block the COX-1 enzyme, production of thromboxane and some anti-inflammatory prostaglandins is decreased, and in patients with aspirin-induced asthma this results in the overproduction of pro-inflammatory leukotrienes to causes severe exacerbations of asthma and allergy-like symptoms.