Willingness to pay for antipsychotic medications in two tertiary health institutions in Nigeria

Abstract

Objectives: Antipsychotic medications availability and affordability enhance patients' compliance and consequently improving their productivity. In Nigeria, where about half the number of her population is impoverished, and health-care cost burden is mostly out of pocket of patients. The study objectives are to determine patients' preference in three antipsychotic medications with different attributes and side/adverse effects and a hypothetical antipsychotics medication with highest efficacy and highest risk, which of the drug's willingness to pay (WTP) price is closer to the actual amount of the medication, as well as the demographic factors that influence WTP of antipsychotic medications. Methods: WTP instrument was administered to 706 consenting patients. The characteristics ranging from efficacy, duration of administration, and possibility of eliciting side/adverse effects of the drugs was provided. A contingent valuation method was used where a virtual market scenario of 20 payment options was presented to the patients with different prices ranging from N 100 ($ 0.33) to NGN5000 (USD16.67). As at the time of this study, $1 (USD) was equivalent to N300.00 (NGN). A linear multivariate analysis was employed to determine the influence of sociodemographic factors on WTP. Results: At most of the given prices, more patients were willing to pay for the hypothetical antipsychotic D. The WTP for all the medications except haloperidol indicated by most of the respondents were above their reference prices. Longer duration of previous treatment, higher educational status, higher income, and stable marital status gave P = 0.001, P = 0.015, P < 0.001, and P = 0.002, respectively. Conclusion: Patients preferred the medication that has the highest efficacy and attendant risk; majority of the patients are willing to pay at a lower price than the prevailing price for all medications used except haloperidol. The duration of previous drug treatment, income, age, education, and marital status significantly affected the WTP of drugs.