Formulation of extended release orphenadrine citrate tablets to treat muscle spasm and pain

Abstract

Objective: Orphenadrine is an anticholinergic, antimuscarinic, centrally acting skeletal muscle relaxant. It presents
in the form of citrate and HCl salts which are used in treatment of the symptoms of mild Parkinson's disease and
also it is used as adjuvant with other drugs in the therapy. Method: Many trials were made to formulate orphenadrine citrate as tablet using wet granulation or direct compression technique in order to get a satisfactory
formula through studying the effect of various factors such as binders, diluents and disintegrants types. The best
formula was obtained by using poly vinyl pyrrolidone (PVP) as a binder also the results indicated that starch and
mannitol gave acceptable physical properties to the tablets when they were used as diluents. At the same time, the
results showed that avicel which was used as a disintegrant gave an acceptable disintegration and dissolution time in comparison with the reference tablet DISIPAL. In addition, the selected formula was used to study the effect of
method of incorporation of disintegrant on the physical properties of tablets. Result: It was found that the
intragranular incorporation resulted in a shorter disintegration and dissolution times. The stability of orphenadrine
citrate prepared tablets was also studied upon storage at 50C, 60C and 70C for four months. Conclusion: The
overall results of this study indicate that the drug can be prepared as tablets, which fit the requirements of British
Pharmacopoeia since the prepared tablets gave satisfactory results.