Formulation and Evaluation of Efavirenz 600 mg Tablet

Aim: Formulation and Evaluation of Efavirenz 600 mg Tablet.

Methodology: Accurately weighed amount of selected additive concentrates (F1, F2, F3, F4, F5, F6) representing 600 mg equivalent of drug was mixed with directly compressible excipients i.e. Croscarmellose Sodium and Sodium Starch Glycolate as superdisintegrants, Talcum as diluents and microcrystalline cellulose as diluents. Obtained mixture was subjected for wet granulation. Water was added and mixed thoroughly to form dough mass. The mass was passed through mesh no. 12 to obtain wet granulation. The wet granules were dried at 60° C for 4 hours. Dried granules were passed through mesh no. 16 to break aggregates. Lubricants talcum and magnesium stearates were passed through mesh no. 100 on to dry granules and blended in a closed polyethylene bag. The tablet granules were compressed by using 16 station tablet compression machine (electrical Motor-Crompton Greaves and A.C. Drives-Siemens) to a hardness of 5-6 kg/cm2 using 9 mm flat punches. In each case 500 tablets were compressed. Prepared tablets were collected in a poly bag.

Results: Evaluation of developed formulation for various pre-compression and post-compression parameters was found to be within pharmacopoeial limits.

Pre-compression parameters of the formulation- Pre-compression parameters were characterized on the basis of their physical parameters. Bulk density (0.338 g/ml), Tapped density (0.458 g/ml), Compressibility ratio (23.89 %), Hausner's ratio (1.38).

Post-compression parameters: Weight variation, hardness and friability pass U.S.P. specification. Tablets of all formulation showed good physical appearance, disintegration test indicated that the tablets of all formulation were dissolved in desire time. Disintegration time of all the formulation have to be less than 45 minute. Disintegration time of the various formulation were found in following order in min F5 (8.10±0.39)>F6 (8.15±0.42)>F3 (8.33±0.43)> F2 (8.35±0.46)> F4 (8.37±0.47)> F1 (8.40±0.43).

This is due to F5 and F6 contain maximum concentration of superdisintegrants (CCS-8.5%, SSG-9.2%), than followed by other formulation. Weight variation tests, hardness and friability test indicated that, tablets of all formulation were having good compactness and mechanical strength and passes U.S.P. specification.

In-vitro dissolution studies revealed that the release rate of Efavirenz coated tablets were found to be in following order F6>F5>F4>F3>F2>F1. This is due to F6 contain maximum concentration of superdisintegrants concentration.