Pathogens that are resistant to medications develop more quickly than new drugs originate from drug research pipelines. Therefore, it is important to better safeguard the treatment options available today and in the future. To do this, it is important to comprehend the factors that lead to the development of drug resistance over time. For the majority of bacteria, many of these parameters are fairly well recognised, but for parasites carried by vectors, the situation is more complicated. We explore how drug resistance can develop, disseminate, and persist using three major models (Plasmodium, Leishmania, and Schistosoma ). We present a variety of scenarios that are clearly a result of the biological diversity of the various organisms, as well as the various routes of action of the drugs used, the unique ecology of the parasites within and between hosts, and environmental factors that could have direct or indirect effects. Given the effects of antibiotic resistance on human health, clinical researchers are very interested in studying this issue. In addition, one of the few evolution instances that can be tracked in real time is antibiotic resistance. Therefore, clinical professionals, evolutionary biologists, and ecologists are interested in understanding the general principles involved in the acquisition of antibiotic resistance. Environmental microorganisms are the source of the genes that human infections now have that make them resistant to antibiotics. The study of both clinical ecosystems and natural habitats is necessary to understand how antibiotic resistance evolves. The founder effect, ecological connection, and fitness costs are significant bottlenecks that control the transfer of resistance from ambient microbes to diseases, according to newly available evidence on the evolutionary mechanisms behind resistance.