Contraindication.

A condition that makes a treatment inadvisable.

A contraindication is a circumstance in which a treatment should not be used because the expected risk outweighs the expected benefit. The distinction usually drawn is between absolute contraindications, where the treatment should not be given at all, and relative contraindications, where it may still be appropriate if the benefit is large enough and the situation is monitored. Contraindications come from a known interaction between the drug's mechanism and a particular condition, medication, or life stage, and they are one of the main reasons prescribing is a clinical decision rather than a lookup. The relevance to this field is direct. Approved peptide-based drugs carry documented contraindications derived from trial data and post-marketing surveillance, covering situations such as specific personal or family medical histories, pregnancy, and interactions with other treatments. Compounds sold for research use carry no such documentation, not because none exist but because nobody has done the work to identify them. The misunderstanding worth correcting is treating an empty contraindication list as a clean bill of health. For an untested compound, the list is empty because the studies that would populate it were never run, which is the opposite of reassurance.