NonMaleficence

Nonmaleficence is an ethical principle requiring individuals and institutions to avoid causing harm to others. It derives from Latin primum non nocere (first, do no harm) and has ancient roots in the Hippocratic tradition; in modern ethics it is codified as a formal moral obligation.

In biomedical ethics, nonmaleficence is a core duty alongside beneficence. It emphasizes avoiding harm, minimizing potential harms from interventions, and ensuring that any potential benefits outweigh risks. It supports informed consent, patient safety, risk assessment, and the precautionary approach.

In clinical practice, it guides decisions such as withholding or withdrawing treatments, dosing regimens to minimize adverse effects, and protecting vulnerable patients. The principle interacts with beneficence; sometimes preventing harm conflicts with providing benefit, requiring careful deliberation and patient preferences.

The Double Effect principle is often invoked when an action with beneficial aims also causes harm incidentally. Proportionality and reasonable foreseeability matter; harm must not be intended and the benefit must be proportionate to the risk.

In research and policy, nonmaleficence requires risk minimization, monitoring, and independent ethics review. Limitations include ambiguity in scope, cultural variation, possible paternalism, and the challenge of balancing harms against other duties like autonomy, justice, or social welfare.