Concurrent fungal infections in the current area have been an unaddressed issue due to the resistance of the host fungal organism to the present antifungal ailments available in the market. Posaconazole is the drug of choice for prophylactic fungal infection and is also recommended in immunecompromised patients in prophylaxis of candida and aspergillus infections including patients undergoing hematopoietic stem cell transplantation that has graft versus host disease. Hence the aim is to formulate a microemulsion based formulation of posaconazole to deliver the drug at the site of action with a quick onset of action compared to suspension formulation at an affordable cost. Methodology: Posaconazole microemulsion was formulated using a pseudo ternary phase diagram and optimized using a D-optimal design. The formulation was characterized for % drug content, pH, globule size, zeta potential, PDI value and in-vitro drug release and stability study at 40°C/75% RH for six months. Results: The oral posaconazole microemulsion had a drug content of more than 95%, pH of 7.2. The globule size, zeta potential and PDI value were found to be 74 nm, 12.45 mV and 0.122 µs.cm-1 indicating a stable microemulsion. The drug release of the ME was more than 90% in fifteen minutes indicating the quick onset of action and availability at the site of action. Conclusion: From the obtained results, it can be said that a stable posaconazole oral microemulsion with a quick onset of action and better bioavailability can be manufactured at affordable cost which can enhance patient compliance

Posaconazole, microemulsion, anti-fungal