median lethal dose

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median lethal dose


mean lethal dose

1. (Medicine) the amount of a drug or other substance that, when administered to a group of experimental animals, will kill 50 per cent of the group in a specified time
2. (Medicine) the amount of ionizing radiation that will kill 50 per cent of a population in a specified time
Abbreviation: LD50

me′dian le′thal dose′

the quantity of a lethal substance, as a poison or pathogen, or of ionizing radiation that will kill 50 percent of the organisms subjected to it in a specified time period. Symbol: LD50
References in periodicals archive ?
In drugs with a narrow therapeutic index, there is usually less than a twofold difference between the median lethal dose and the median effective dose.
Acute and sub-chronic studies were carried out and median lethal dose (LD50) of the extract was found to be 3.