Up-and-down procedure (or method) for toxicology tests in medicine is an alternative to the LD50 test, in which animals are used for acute toxicity testing. [1] [2] It requires fewer animals to achieve similar accuracy as the LD50 test because animals are dosed one at a time. [3] If the first animal survives, the dose for the next animal is increased; if it dies, the dose is decreased. It is usual to observe each animal for 1 or 2 days before dosing the next animal, however, surviving animals should be monitored for 7 days in case of delayed death. The up-and-down method is not recommended where deaths beyond 2 days are the norm. [4] The U.S. Food and Drug Administration has begun to approve non-animal alternatives. [5] [6]
Up-and-down procedure (or method) for toxicology tests in medicine is an alternative to the LD50 test, in which animals are used for acute toxicity testing. [1] [2] It requires fewer animals to achieve similar accuracy as the LD50 test because animals are dosed one at a time. [3] If the first animal survives, the dose for the next animal is increased; if it dies, the dose is decreased. It is usual to observe each animal for 1 or 2 days before dosing the next animal, however, surviving animals should be monitored for 7 days in case of delayed death. The up-and-down method is not recommended where deaths beyond 2 days are the norm. [4] The U.S. Food and Drug Administration has begun to approve non-animal alternatives. [5] [6]