alpha-asarone and isopropyl-myristate

A transdermal drug delivery system has been reported that can increase the bioavailability, reduce the administration duration, and maintain the concentration of drug in blood. In the present study, drug-in-adhesive transdermal patches of α-asarone using Eudragit E100 as pressure-sensitive adhesives and oleic acid plus isopropyl myristate as penetration co-enhancers were developed. In vitro permeation, in vivo pharmacokinetics in rabbits, and efficacy in asthmatic rats were evaluated. The results showed that co-enhancers could induce a synergistic effect on α-asarone permeability. In vivo study suggested that the patch can keep a relatively certain blood level of drug within 10-30 h in rabbits. Furthermore, the patch with the size of 4 cm² containing drug 3 mg/cm² showed a noticeable treating effect on asthmatic rats which is equivalent to the effect of dexamethasone, while avoiding the side-effect induced by the corticorsteroid. This suggests that the drug-in-adhesive transdermal patch is a promising delivery system containing α-asarone to be used for asthma treatment.

Topics: Acrylates; Adhesives; Allylbenzene Derivatives; Animals; Anisoles; Asthma; Biological Availability; Chemistry, Pharmaceutical; Delayed-Action Preparations; Drug Synergism; Inflammation; Myristates; Oleic Acid; Permeability; Polymers; Rabbits; Rats; Rats, Sprague-Dawley; Skin; Skin Absorption; Transdermal Patch

To prepare the alpha-asarone reservoir patch and investigate its release and transdermal absorption characteristics in vitro. The efficient enhancers were chosen to improve the drug's permeation rate.. The alpha-asarone reservoir patch was prepared using 1% hydroxypropyl methylcellulose (HPMC) of ethanol solution as medium and ethylene vinyl acetate (EVA) membrane to control the release of drug. The Franz diffusion cells were used and several permeation enhancers were evaluated. High performance liquid chromatorgraphy (HPLC) was used to determine alpha-asarone's content and permeation rate.. The release mechanisms of alpha K-asarone patch in vitro coincided with zero-order kinetic. 30% ethanol cooperates with 1% Isopropyl Myristate (IPM) have the best effect on permeation of the patch. The permeation rate reaches (20.67 +/- 1.33) microg x cm(-2) h(-1).. Ethanol combined with IPM is good permeation enhancer, which facilitated the permeation of alpha K-asarone to fit the clinical requirements. However, the further studies of the skin's stimulation and bioavailability are needed.

Topics: Acorus; Administration, Cutaneous; Allylbenzene Derivatives; Anisoles; Delayed-Action Preparations; Ethanol; Humans; Hypromellose Derivatives; In Vitro Techniques; Methylcellulose; Myristates; Plants, Medicinal; Polyvinyls; Skin; Skin Absorption