Monti Plus Mechanism of Action

Pharmacology: As Montelukast Sodium + Levocetirizine Hydrochloride is a combination of Montelukast and Levocetirizine; the pharmacological properties of both the molecules are given separately: Montelukast sodium is a selective and orally active leukotriene receptor antagonist that inhibits the cysteinyl leukotriene (CysLT1), receptor.
Levocetirizine is the R-enantiomer of cetirizine. Levocetirizine is an orally active, potent, selective and long acting H1-histamine receptor antagonist with no anticholinergic activity.
Studies have demonstrated that Allergic Rhinitis [AR] when treated concomitantly with an antileukotriene (Montelukast) and an antihistamine (Levocetirizine), shows significantly better symptom relief compared with the modest improvement of rhinitis symptoms with each of the treatments alone.
Pharmacokinetics: Peak plasma concentrations of Montelukast are achieved in 3 to 4 hours after oral doses. The mean oral bioavailability is 64%. Montelukast is more than 99% bound to plasma proteins. It is extensively metabolised in the liver by cytochrome P450 isoenzymes CYP3A4, CYP2A6, and CYP2C9, and is excreted principally in the faeces via the bile.
Levocetirizine is rapidly absorbed from the gastrointestinal tract after oral doses, peak plasma concentrations being attained within about an hour. Food delays the time to peak plasma concentrations but does not decrease the amount of drug absorbed. Levocetirizine is highly bound to plasma proteins and has an elimination half-life of about 10 hours. It has been detected in breast milk. Levocetirizine is excreted primarily in the urine mainly us unchanged drug. It does not appear to cross the blood-brain barrier to a significant extent.