| umls-concept:C0013203 | skos:definition | MSH: Diminished or failed response of an organism, disease or tissue to the intended effectiveness of a chemical or drug. It should be differentiated from DRUG TOLERANCE which is the progressive diminution of the susceptibility of a human or animal to the effects of a drug, as a result of continued administration.,CSP: tendency of biological systems (organisms, cells, or cell-free systems) to fail to respond as expected to drug treatment or exposure; may be due to specific enzymes, transporters, or receptors which block drug action.,GO: OBSOLETE (was not defined before being made obsolete). [GOC:go_curators],NCI: Mechanisms, functions, activities, or processes exhibited by tumors or pathogens to withstand previously toxic drugs.,NCI: The failure of cancer cells, viruses, or bacteria to respond to a drug used to kill or weaken them. The cells, viruses, or bacteria may be resistant to the drug at the beginning of treatment, or may become resistant after being exposed to the drug. | lld:umls |
