Formulation and evaluation of fast dissolving tablets of haloperidol solid dispersion

PURPOSE: The aim of this study was to design fast dissolving tablets (FDT) of the anti –psychiatric drug haloperidol in solid dispersion forms as a way to enhance its dissolution profile and anti-psychiatric effect. METHODS: Solubility studies of haloperidol in various polymers solutions were investigated. The selected polymer with high drug solubility (Poly ethylene glycol 4000) was used for preparation of solid dispersion through two methods solvent evaporation method and melting method. Haloperidol solid dispersion mixed with other solid powder excipients and compressed into tablets. The resulted tablets were evaluated according to British Pharmacopoeia (B.P.) specifications. Pre- and post -compression studies were performed to determine the flow properties and evaluate the solid dispersion systems, followed by in vivo studies through forced swimming test (FST) RESULTS: Pre-compression studies showed adequate flowability and compatibility of polymer and solid excipients with haloperidol. The selected solid dispersion tablet (SD2) demonstrated the best disintegration and water absorption ratio in addition to satisfactory friability and hardness. Attempts of in vitro dissolution results and thermodynamic stability studies showed acceptable results for (SD2) formulation containing PEG 4000 polymer prepared by melting method.The in vivo study of (SD2) formulation revealed the highest immobility time to rats compared to control rats and others treated with commercial haloperidol product. CONCLUSION: Fast dissolving tablets prepared from solid dispersion of haloperidol with PEG4000 expressed rapid onset of action with enhanced anti-psychiatric effect of haloperidol.