Gastro retentive Drug Delivery of Cyclobenzaprine Hydrochloride

Drugs that are easily absorbed from the GI tract and have a short half-life are eliminated quickly from the blood circulation, require frequent dosing. To avoid this problem, the oral controlled release formulations are being developed. Gastro-retentive dosage forms have the potential from use as controlled release systems. The purpose of this research is to develop the gastro retentive drug delivery system of centrally acting alpha adrenergic agonist cyclobenzaprine Hydrochloride (cyclobenzaprine HCl). It is well absorbed from the upper part of the GIT, due to short gastric residence time the bioavailability is low and hence it is need to develop a dosage form that releases the drug in stomach using gastro retentive system. Different formulations of cyclobenzaprine HCl gastro-retentive floating tablets were prepared by wet granulation method using various concentrations of HPMC K4M / HPMC K100M and combination of Psyllium husk and HPMC K100M as matrix forming agent. Sodium bicarbonate and citric acid were used as a gas generating agent that helps in maintaining the buoyancy. The prepared cyclobenzaprine HCl gastro-retentive floating granules were subjected to pre-compression properties to comply with pharmacopoeial limits and the prepared gastro-retentive floating tablets were characterized for weight variation, hardness, thickness and friability drug content, swelling studies. The floating lag time of all formulation is good and the Total floating time of all the formulations was >12 hours. The tablets were evaluated for in vitro release characteristics for 12hrs in 0.1N HCl at 37 oC and from this in vitro release studies the formulations F-5, F-9 and F-15 exhibited good controlled release profile of about 96.0%, 94.5% and 95.0% when compared with other formulations while floating on the dissolution medium.