Montelukast

Category: pharmacological

Aliases: Singulair

Pharmacological Mechanism

Leukotriene CysLT1 receptor antagonist — blocks LTD4 / LTE4 bronchoconstriction. Adjunctive asthma + allergic rhinitis. FDA black-box (2020) for neuropsychiatric adverse events including suicidality.

Half-Life (t½)

PO: 4h

Dosing Guidelines

• PO: Typical 10 mg (Range: 4–10 mg)

Target Organ Systems

• respiratory
• immune-hematologic

Pathways It Modulates

• Airway smooth-muscle tone (inhibitor) — CysLT1 → blocks leukotriene bronchoconstriction
• Arachidonic acid cascade (inhibitor) — CysLT1 receptor (downstream of LTC4/D4/E4)
• Asthma (inhibitor) — CysLT1 receptor (leukotriene antagonist)

Chemical Identifiers

• PubChem CID: 5281040
• Formula: C35H36ClNO3S
• Molecular weight: 586.18 g/mol
• InChIKey: UCHDWCPVSPXUMX-TZIWLTJVSA-N
• SMILES: CC(C)(C1=CC=CC=C1CC[C@H](C2=CC=CC(=C2)/C=C/C3=NC4=C(C=CC(=C4)Cl)C=C3)SCC5(CC5)CC(=O)O)O

References

• PMID 7621356