Ritolukast

Ritolukast is a leukotriene receptor antagonist that is primarily used in the management of asthma and allergic rhinitis. It functions by blocking the action of leukotrienes, which are inflammatory chemicals the body releases after coming in contact with an allergen or irritant. By inhibiting these chemicals, ritolukast helps to reduce inflammation, bronchoconstriction, and mucus production in the airways.

Mechanism of Action

Ritolukast works by selectively binding to cysteinyl leukotriene receptors, particularly the CysLT1 receptor, which is found in the human airway smooth muscle cells and other tissues. Leukotrienes are derived from arachidonic acid and are potent mediators of inflammation. By blocking these receptors, ritolukast prevents leukotrienes from exerting their effects, thereby reducing airway inflammation and bronchoconstriction.

Pharmacokinetics

Ritolukast is administered orally and is well absorbed from the gastrointestinal tract. It undergoes extensive metabolism in the liver, primarily by the cytochrome P450 enzyme system. The drug is excreted mainly in the feces, with a smaller portion eliminated via the urine. The elimination half-life of ritolukast is approximately 5 to 7 hours, allowing for once or twice daily dosing.

Clinical Uses

Ritolukast is indicated for the prophylaxis and chronic treatment of asthma in adults and children over the age of 12. It is also used to relieve symptoms of allergic rhinitis, such as nasal congestion, sneezing, and runny nose. Ritolukast is not indicated for the relief of acute asthma attacks.

Adverse Effects

Common side effects of ritolukast include headache, dizziness, nausea, and abdominal pain. Rare but serious side effects may include liver dysfunction and hypersensitivity reactions. Patients are advised to report any signs of liver problems, such as jaundice or dark urine, to their healthcare provider.

Drug Interactions

Ritolukast may interact with other medications that are metabolized by the cytochrome P450 system, such as warfarin, phenytoin, and theophylline. It is important to monitor patients for potential interactions and adjust dosages accordingly.

Also see

• Leukotriene receptor antagonist
• Asthma
• Allergic rhinitis
• Cysteinyl leukotriene receptor
• Arachidonic acid