Consumer willingness to pay for a pharmaceutical disposal program in Serbia: A double hurdle modeling approach.

Proper collection and disposal of pharmaceutical waste from households can reduce the negative influence of medicines on the environment. The aim of this paper is to examine the current methods of disposal of unused medicines from households, as well as the willingness of Serbian residents to participate and bear the costs of an organized collection program. Moreover, this research aims to define factors contributing to an individual's willingness to participate and pay for a medicine collection program. The survey included randomly selected patients older than 18 years visiting private pharmacies in the four largest Serbian cities. The questionnaire included information regarding the presence of unwanted medicines within the household, general medicine disposal practices, the likelihood to participate in a medicine take-back program, willingness to pay for a medicine disposal program (per prescription and per visit), importance to the environment, and demographic variables from participants. Approximately 80% of surveyed respondents are very or somewhat likely to participate, however less than half of the respondents are willing to pay for the collection of their unused medicines. The factors that influenced willingness to participate are environmental awareness and income, while the factors affecting willingness to pay, are previously received advice about proper disposal, education level, number of unwanted medicines in the household and gender. The majority of Serbian people dispose unused medicines improperly, mostly into household garbage. Well-organized and easily accessible collection programs are essential in order to enable the general public to return unused medicines for proper disposal.