Chemical Properties
Rupatadine is off white to pinkish crystalline powder. It is soluble in methanol and ethanol slightly soluble in Chloroform and insoluble inwater.
Uses
Rupatadine Fumarate is a dual antagonist of histamine H1 and platelet-activating factor receptors. Rupatadine fumarate has been approved for the treatment of allergic rhinitis and chronic urticaria in adults and children over 12 years.
Uses
Rupatadine is an intermediate in the synthesis of Rupatadine (5-Methyl-3-pyridinyl)methyl)pyridinium Chloride (M326740). (5-Methy-3-pyridinyl)methyl-Rupatadine is an impurity of Rupatadine (R701650), a dual antagonist of histamine H1 and platelet-activating factor receptors
Definition
ChEBI: Rupatadine is a benzocycloheptapyridine.
Biological Activity
Rupatadine is an antagonist of histamine H1 and platelet-activating factor (PAF) receptors. It binds to rabbit platelet membranes and guinea pig cerebellum membranes with apparent Ki values of 0.55 and 0.1 μM, respectively, in radioligand binding assays. It inhibits contraction of isolated guinea pig ileum induced by histamine (pA2 = 9.29) and platelet aggregation induced by PAF in washed rabbit platelets (pA2 = 6.68). Rupatadine prevents histamine- or PAF-induced hypotension in rats (ID50s = 1.4 and 0.44 mg/kg, respectively) and reverses histamine- or PAF-induced bronchoconstriction in guinea pigs (ID50s = 113 and 9.6 mg/kg, respectively). It does not reduce locomotor activity or potentiate sleep induced by barbiturates in mice, indicating a lack of sedative effects.
Pharmacokinetics
Rupatadine was rapidly absorbed after oral administration, with a time taken to reach the maximum plasma concentration (Tmax) of 1 hour (median value). The maximum plasma concentration (Cmax) obtained after single and repeated doses of 10 mg rupatadine were from 1.54 to 4.03 ng/mL and from 1.99 to 4.74 ng/mL respectively. Steady state was reached by the fifth day of therapy without extensive accumulation and the plasma concentration-time curve during a time dose interval (AUCτ) ranged from 8.37 to 16.2 ng.h/mL. Pharmacokinetics of rupatadine was linear for a dose between 10 and 20 mg after single and repeated doses. The plasma concentration followed a bi-exponential drop-off with a mean elimination half-life after a single dose of 6.1 hours.
Side effects
Common side effects (may affect up to 1 in 10 people):
Sleepiness, headache, dizziness, dry mouth, sensation of weakness and fatigue.
Uncommon side effects (may affect up to 1 in 100 people):
Increased appetite, irritability, difficulty concentrating, nosebleed, nasal dryness, sore throat, cough, dry throat, rhinitis, nausea, abdominal pain, diarrhoea, indigestion, vomiting, constipation, rash, back pain, joint pain, muscle pain, thirst, general discomfort, fever, abnormal liver function test and increased weight.
Mode of action
Rupatadine is a second generation, non-sedating, long-acting histamine antagonist with selective peripheral H1receptor antagonist activity. It further blocks the receptors of the platelet-activating factor (PAF) according to in vitro and in vivo studies.
Rupatadine possesses anti-allergic properties such as the inhibition of the degranulation of mast cells induced by immunological and non-immunological stimuli, and inhibition of the release of cytokines, particularly of the tumor necrosis factors (TNF) in human mast cells and monocytes.
