Anti-leukotrienes in asthma: yet to arrive.

Inflammation plays a predominant role in the pathogenesis of asthma. The leukotrienes (LTs) exert their actions by binding to and activating various receptors. Leukotrienes B4, C4, D4, and E4 have been shown experimentally to play a role in inflammatory mechanisms, producing the pathologic changes seen in asthma. Antileukotrienes represent a new class of anti-asthma drugs with anti-inflammatory role. In asthma management, LT modifiers from the groups of 5 lipoxygenase inhibitor and Cys LT1 receptor antagonists are found useful. LAs are of main use in mild to moderate chronic asthma. Their usefulness is also observed in allergic rhinitis and even in severe chronic cases of asthma which are resistant to steroids. In chronic asthma they are required to be used for prolonged periods with other agents viz. inhaled steroids and beta 2 agonists. These agents are essentially safe. Except for Montelukast, which can be used in children above six years of age, the paediatric use of other agents is yet to be established. LAs are gradually becoming available in increasing number of countries. In India, we have to presumably wait for sometime before these drugs reach the market. The cost of LAs is reasonably high. Thus, India awaits arrival of LAs, may be for good, as more concrete information from various trials will permit us to practice more evidence based medicine.