Protozoan infections (e.g., malaria, trypanosomiasis, and toxoplasmosis) pose a considerable global burden on public health and socioeconomic problems, leading to high rates of morbidity and mortality. Due to the limited arsenal of effective drugs for these diseases, which are associated with devastating side effects and escalating drug resistance, there is an urgent need for innovative antiprotozoal drugs. The emergence of drug repurposing offers a low-cost approach to discovering new therapies for protozoan diseases. In this review, we summarize recent advances in drug repurposing for various human protozoan diseases and explore cost-effective strategies to identify viable new treatments. We highlight the cross-applicability of repurposed drugs across diverse diseases and harness common chemical motifs to provide new insights into drug design, facilitating the discovery of new antiprotozoal drugs. Challenges and opportunities in the field are discussed, delineating novel directions for ongoing and future research.

Acute high-altitude (HA) illnesses (AHAIs), including acute mountain sickness (AMS), HA cerebral edema (HACE), and HA pulmonary edema (HAPE), represent significant health challenges for individuals rapidly ascending to high altitudes. Cytokines (interleukins (ILs)) and chemokines, which are involved in inflammatory and immunological responses, regulate the response of the body to hypoxic stress. Their dysregulation can contribute to the clinical symptoms of AMS, HACE, and HAPE by increasing vascular permeability, causing edema and damaging tissue. AHAIs elevate the levels of pro-inflammatory cytokines and chemokines, such as IL-17, tumor necrosis factor α (TNF-α), IL-1, IL-6, C-X-C motif chemokine ligand (CXCL) 10, CXCL8, C-C motif ligand 2 (CCL2 (CCL2), and CCL3, exacerbating symptoms. Thus, this review focuses on the cytokines and chemokines involved in AHAIs and the molecular mechanisms that extend beyond these cytokines and chemokines in clinical and preclinical contexts. Identifying these mediators and pathways helps researchers design drugs that reduce symptoms, slow disease progression, and enhance outcomes. Cytokines and chemokines have complex functions in these disorders and may serve as prospective therapeutic targets. Finally, we discuss treatment possibilities for AHAIs (drugs, exercise, and other inhibitors). This knowledge will help us to protect and improve the health of individuals at high altitudes.