Comparative Study of Different Combinational Mucoadhesive Formulations of Sumatriptan-Metoclopramide

Purpose: Sumatriptan succinate (Sum) is a Serotonin 5- HT1 receptor agonist, used in the treatment of migraine. It is absorbed rapidly but incompletely when taken orally and underwent first - pass metabolism, resulting in a low bioavailability of about 15%. The aim was to design mucoadhesive buccal discs and sublingual films of Sum and metoclopramide (Met) combined to improve their bioavailability. Methods: In the current study, the microparticles and films were prepared by emulsion solvent diffusion (ESD) and solvent casting methods, respectively. Buccal-mucoadhesive microparticles and films with different drug to polymer ratios were prepared and characterized by encapsulation efficiency, particle size, DSC (Differential Scanning Calorimetric), folding endurance, mucoadhesive property and drug release studies. Results: The best drug/s to polymer ratios in films and microparticles were 1:2.7:8 (SM(2)) and 1:4:6 (SM(4)), respectively. The film of SM(2) showed 11.01 mg weight, 123 µm thickness and 300 folding endurance. The production yield was 107.33% for SM(4) microparticles, 323.59 µm for mean particle size and 94.53% for loading efficiency (for Sum) and 104.18% (for Met). The DSC showed no stable characteristic of Sum and Met in the drug loaded films/discs and revealed amorphous form and transition of hydrate to anhydrous form for Met. The films exhibited very good mucoadhesive properties and shorter retention time (15-30 s) in comparison with the discs (130 min). The results showed that the discs prepared had slower release than the films (p<0.05). Conclusion: Films and discs of Sum-Met combinations were successfully prepared with improved release and mucoadhesive properties.