Compound Hydrochloric Acid Cetirizine Cinnarizine Sustained-release Capsules

Cetirizine,a metabolite of hydroxyzine,is an antihistamine;its principal effects are mediated via selective inhibition of H₁ receptors. The antihistaminic activity of cetirizine has been clearly documented in a variety of animal and human models. In vivo and Ex vivo animal models have shown negligible anticholinergic and antiserotonergic activity. In clinical studies,however,dry mouth was more common with cetirizine than with placebo. In vitro receptor binding studies have shown no measurable affinity for other than H₁ receptors. Autoradiographic studies with radiolabeled cetirizine in the rat have shown negligible penetration into the cetirizine does not significantly occupy cerebral H₁ receptors.Pseudoephedrine hydrochloride is a orally active sympathomimetic amine and exerts a decongestant action on the nasal mucosa. Pseudoephedrine hydrochloride is recognized as an effective agent for the relief of nasal congestion due to allergic rhinitis. Pseudoephedrine produces peripheral effects similar to those of ephedrine and central effects similar to,but less intense than,amphetamines.It has the potential for excitatory side effects.In one study,cetirizine 5mg plus pseudoephedrine SR 120mg was significantly more effective at reducing nasal obstruction than either drag alone. The bioavailability of Cetirizine and Pseudoephedrine is similar after administration of Cetirizine/Pseudoephednne 5/120mg bilayer tablets or coadministration of cetirizine 5mg tablets plus Pseudoephedrine sustained releasa (SR) 120mg caplets. The compoud sustained-release capsules of twice daily administration was designed and prepared.Pseudoephedrine pellets were prepared by means of power layering by the centrifugal coating and granulation equipment. Eudragit NE 30D was used as coating materials and coating process was performed by the same equipment. The effects of process variables and formulation variables on coating pellets preparation were investigated. The results showed the coated pellets had a marked sustained-release property.Using Zyrtec-D 12Hour as the reference,thepharmacokinetics in dogs of compound sustained-release capsules were studied. The result of comparison between the compound sustained-release capsules and Zyrtec-D 12 Hour indicated that Cmax was lower informer. The results showed that the compound sustained-release capsules had satisfactory sustained-release effects and there were good correlation between absorpation percent in vivo and accumulative release in vitro.