Leukotriene D4 and Lidocaine

Leukotriene D4 (LTD4) is a naturally occurring inflammatory mediator that functions as a potent bronchoconstrictor and is implicated in asthma pathophysiology. It is one of the cysteinyl leukotrienes released from activated mast cells and basophils. LTD4 is formed when LTA4 is conjugated with glutathione in cells expressing LTC4 synthase, and it acts on CysLT1 and CysLT2 receptors on target cells. Lidocaine is an amide-type local anesthetic used for local or regional anesthesia through various administration techniques including infiltration, peripheral nerve blocks, and central neural techniques. It is completely absorbed following parenteral administration, with absorption rates depending on lipid solubility and the presence of vasoconstrictor agents. Lidocaine crosses blood-brain and placental barriers through passive diffusion. **It is important to note that the search results do not describe 'Leukotriene D4 + Lidocaine' as a specific combination product or pharmaceutical formulation.** Instead, these substances are mentioned separately, with one study examining the mechanism of leukotriene D4-induced bronchoconstriction in subjects pretreated with various agents including lidocaine. This research indicated that lidocaine had no effect on either baseline lung function or the airway response to LTD4, suggesting that LTD4-induced bronchoconstriction in normal subjects is not mediated by irritant receptors in the upper airways.