How do animal tests help scientists identify a drug's possible toxicity?

Animal testing serves as a preclinical method to evaluate the safety and potential toxicity of new medications before they are administered to humans. Scientists use these studies to identify suitable lead chemicals and determine appropriate dosages for further development.123

The process typically involves several types of toxicity assessments:

• Acute Toxicity Studies: A single large or potentially toxic dose is administered to two mammalian species via the intended route of human use. Animals are observed for one to four weeks to evaluate organ and tissue toxicity.4
• Subchronic and Chronic Studies: These involve daily administration of the drug for up to three months or longer, respectively. They are designed to detect neurological, physiological, biochemical, and hematological abnormalities.4
• Specialized Testing: Depending on the intended duration of human use, researchers may conduct studies on carcinogenicity (potential to cause cancer), reproductive and developmental toxicity, and mutagenicity.43

While these tests are used to screen for risks, it is important to note that they are not always predictive of human outcomes, and ethical concerns regarding animal welfare remain a significant subject of debate. Regulatory frameworks, such as the FDA Modernization Act 2.0, have recently shifted to make animal testing an option rather than a mandatory requirement for pharmaceutical companies.156