This study examines the factors influencing the prescribing decisions of Filipino ophthalmologists decisions using a mixed methods approach that combines conjoint analysis and phenomenology. 318 respondents participated in the conjoint analysis, and 7 took part in key informant interviews. Path-worth analysis was the statistical treatment utilized for conjoint analysis. Respondents favored generic medications with a strong corporate image and products with purite/polyquad preservatives. Regular interactions with medical representatives, emphasizing personal relationships, were also valued, while patients' economic status had minimal impact on prescribing decisions. This study uniquely explored the factors behind Filipino ophthalmologists' prescribing behaviors. It introduces the "preservative" characteristic of ophthalmic drugs, marking a potentially first-of-its-kind investigation in the Philippines and worldwide.