Comparative study of different approaches for preparation of chlorzoxazone orodispersible tablets.

CONTEXT: Muscle spasm is a painful involuntary contraction of muscles, which causes involuntary movement and distortion. Chlorzoxazone is a centrally acting muscle-relaxant with sedative properties, but given orally, it is hepatically metabolized leading to decreased bioavailability. OBJECTIVE: Orodispersible tablets (ODTs) of chlorzoxazone were formulated using two different approaches; by coprocessed excipients (CE) or by liquisolid (LS) technique. MATERIALS AND METHODS: Pharmaburst® 500, Starlac®, Pearlitol flash®, Prosolv® odt and F-melt® were used as coprocessed superdisintegrants, whereas in LS, Avicel® PH101, Microcelac® 100 and Cellactose® 80 were used as carriers, while Aerosil® 200 was the coating material. ODTs were evaluated in terms of weight and thickness variations, drug content, hardness, friability, wetting time, dissolution, disintegration time (DT) and palatability. RESULTS: In vitro DT of CE-ODTs ranged from 26.43 ± 1.693 s to >180 s, whereas it was between 25.42± 0.203 s to >180 s in LS-ODTs. Complete drug release within 15 min was attained by CE1 prepared with 92.5 mg Pharmaburst® 500. In vivo DT of CE1 and LS3 were 19.779 ± 0.810 and 18.105 ± 0.423 s, respectively, using six volunteers. Volunteers found that CE1 had more acceptable taste and was more palatable than LS3. CONCLUSION: It was concluded that chlorzoxazone ODTs could be successfully formulated using either CE or LS techniques and be used as novel dosage forms for pediatrics and geriatrics showing improved drug release. Moreover, CE technique was superior to LS technique in terms of palatability.

A pharmaceutical study on chlorzoxazone orodispersible tablets: formulation, in-vitro and in-vivo evaluation.

CONTEXT: Muscle spasm needs prompt relief of symptoms. Chlorzoxazone is a centrally muscle relaxant. OBJECTIVES: The aim of this study was to prepare chlorzoxazone orodispersible tablets (ODTs) allowing the drug to directly enter the systemic circulation and bypassing the first-pass metabolism for both enhancing its bioavailability and exerting a rapid relief of muscular spasm. MATERIALS AND METHODS: ODTs were prepared by direct compression method using Pharmaburst®500, Starlac®, Pearlitol flash®, Prosolv® odt and F-melt® as co-processed excipients. Three ratios of the drug to the other excipients were used (0.5:1, 1:1 and 2:1). RESULTS AND DISCUSSION: All ODTs were within the pharmacopeial limits for weight and content. ODTs containing Pharmaburst®500 showed the shortest wetting time (∼45.33 s), disintegration time (DT) (∼43.33 s) and dissolution (Q15min 100.63%). By increasing the ratio of CLZ: Pharmaburst®500 from 0.5:1 to 1:1 and 2:1, the DT increased from 26.43 to 28.0 and 43.33 s, respectively. By using Prosolv® odt, ODTs failed to disintegrate in an acceptable time >180 s. DT of ODTs using different co-processed excipients can be arranged as follows: Pharmaburst® 500 < F-melt®