Could NSAIDs have a role as antiasthmatic agents?

Ibuprofen and increased morbidity in children with asthma: fact or fiction?

NSAIDs are commonly avoided by patients with aspirin-induced asthma based on the premise that there is a significant cross-reactivity between aspirin and other NSAIDs. However, ibuprofen, a NSAID sold over the counter in most countries, is commonly given to children for relief of fever and mild-to-moderate pain. Consequently, increased risk of acute bronchospasm induced by ibuprofen in children with asthma remains a persistent concern. More recently, the assumption that children with asthma are at a greater risk for exacerbations of their disease if they take ibuprofen has been questioned. There is little evidence to measurably increases morbidity in the great majority of children with asthma. In addition, recent evidence suggest that ibuprofen measurably increases morbidity in the great majority of [corrected] children with asthma. Given the infrequent occurrence of aspirin/NSAID sensitivity in children with asthma, it seems reasonable to allow the use of ibuprofen in this population unless there is a personal or family history of aspirin-induced asthma. In addition, the inflammatory pathogenesis of asthma, anti-inflammatory effect of ibuprofen, and evidence suggesting ibuprofen may reduce morbidity in children with asthma raises the intriguing possibility that ibuprofen might actually have therapeutic benefit for at least some children with asthma.

Thromboxane A2 and related prostaglandins in airways

Asthma is now thought to be a chronic inflammatory disease of the airways. The roles of prostanoids, thromboxane A2 (TXA2) and the prostaglandins (PGs) in the pathogenesis and pathophysiology of asthma have fostered a wealth of studies but remain controversial. TXA2 and the bronchoconstrictor PGs, PGD2 and PGF2 alpha, are generated in greater amounts in asthmatic than in normal subjects. TXA2 is a potent constrictor of airway smooth muscle, an inducer of acetylcholine release and of airway microvascular leakage. It may participate in the thickening and the remodeling of the airway wall which may contribute to the airway hyperresponsiveness, a typical feature of asthma. Strategies for inhibition of TXA2 effects include antagonism of the TXA2 receptor (TP receptor) and inhibition of the thromboxane synthase. TP receptor antagonists could block the effects of all the bronchoconstrictor prostanoids because TXA2 as well as the bronchoconstrictor PGs act through activation of lung TP receptor. The recent development of specific and potent TP receptor antagonists and inhibitors of thromboxane synthase has provided tools to assess the role of TXA2 and broncho-constrictor PGs in the pathophysiology of asthma.

Nimesulide in the treatment of patients intolerant of aspirin and other NSAIDs

Aspirin (acetylsalicylic acid) and other NSAIDs are responsible for many adverse effects. Among them, pseudo-allergic reactions (urticaria/angioedema, asthma, anaphylaxis) affect up to 9% of the population and up to 30% of asthmatic patients. The mechanisms provoking these reactions have not been fully elucidated, but it appears that inhibition of cyclo-oxygenase (COX) plays a central role. The anti-inflammatory action of nimesulide differs from that of other NSAIDs, possibly because of its chemical structure. In particular, nimesulide is selective for COX-2 and displays additional properties in terms of its effects on inflammatory mediator synthesis and release. For these reasons, nimesulide is generally well tolerated by NSAID-intolerant patients and patients with NSAID-induced asthma. The good tolerability of nimesulide as an alternative drug for use in patients with NSAID intolerance has been demonstrated in a large number of clinical studies.