Insect self-medication: exploring nature's pharmacy and its role in insect well-being

Self-medication in insects represents a sophisticated adaptive behavioural strategy through which individuals selectively acquire and utilize non-nutritive substances to counteract the deleterious effects of parasites and pathogens. Beyond instinct, insects exhibit deliberate choices that contribute to their health, rather than being reflexive organisms, such as consuming toxic plant compounds, applying topical antimicrobial agents, and modifying nesting environments to limit pathogen exposure. This review integrates contemporary understanding of the classifications and functional mechanisms of self-medication across diverse insect taxa, with emphasis on behavioural, pharmacological, and social dimensions. Evidence of dose-dependent medicinal regulation in insects indicates the existence of sophisticated detection mechanisms, reframing these creatures as active health regulators rather than organisms that merely respond to infection passively. Self-medication involves significant trade-offs, including energetic costs, toxicity risks, reduced growth, and impaired reproduction. Despite these costs, the adaptive value of these behaviours supports survival under pathogenic pressure. Anthropogenic threats such as habitat degradation and ongoing climate variability reduce access to medicinal resources, which affects insect health and population stability. Understanding the ecological and evolutionary context of self-medication supports conservation efforts aimed at preserving plant diversity and microbial resources essential for insect survival.