Piperaquine tetraphosphate tetrahydrate is primarily used as an antimalarial agent, particularly in the treatment and prevention of malaria caused by Plasmodium falciparum. It is often combined with other antimalarial drugs, such as dihydroartemisinin, to enhance its efficacy and reduce the risk of drug resistance. This combination therapy is widely employed in regions where malaria is endemic, providing a potent and effective treatment option. Additionally, it is utilized in mass drug administration programs aimed at controlling malaria outbreaks and reducing transmission rates in high-risk populations. Its long half-life ensures prolonged protection, making it a valuable component in both therapeutic and prophylactic strategies against malaria.