Fish models in experimental pharmacology: on the mark or off the mark?

Fish has emerged as an alternative model organism in biomedical research for conducting experimental pharmacological and toxicological studies. As a vertebrate, it shares many conserved physiological and molecular features with humans making it a valuable model for diagnosing, investigating disease states and testing drugs to check toxicity and therapeutic activity against the target. Zebrafish and medaka are mainstream models that are widely employed in pharmaceutical research. This study aims to highlight the probability and potential of fish as an alternative model organism in biomedical research, drug discovery and development. Further, it discusses the limitations of fish models in experimental pharmacological and toxicological studies considering the changes in the residing environment, physiology, metabolism, unpredictable inter-individual variability due to diseases, variable conditioning, and interspecific and intraspecific variability