International Journal of
MediPharm Research

The present research concerns the formulation and evaluation of sustained release pellets filled capsule of opioid analgesic, Tramadol HCl. Development of sustained release dosage form is to maintain therapeutic blood levels of the drug for extended period of time. Sustained release formulation provides uniform concentration at absorption site, maintains plasma concentration within a therapeutic range, reduces the dosage frequency and minimizes the side effects (nausea) associated with drug by avoiding dose dumping effect. Oral sustained release pellet formulations of Tramadol HCl were prepared using extrusion-spheronization technique. Pellets provide specific advantages of smoother plasma concentration profile and gradual absorption than tablet. Various polymers like Hydroxy propyl methyl cellulose (HPMC K100M), Carbopol 974 P, Xanthan gum, Ethyl cellulose and Eudragit RSPO were used to screen the best polymer combination through preliminary formulations. HPMC K100M, EC and coating of Eudragit RSPO were screened to achieve the aim of sustaining the drug release for 12 hours. The prepared pellets were studied for different flow properties and drug release studies.

Keywords: Tramadol HCl, Sustained release pellets, extrusion-spheronization, HPMC K100M, EC.