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] The U.S. Environmental Protection Agency (US EPA) provides a software program called AOT425StatPgm which calculates the oral LD50 and 95% Confidence Limits. [7]
References
^Lipnick, R.L.; Cotruvo, J.A.; Hill, R.N.; Bruce, R.D.; Stitzel, K.A.; Walker, A.P.; Chu, I.; Goddard, M.; Segal, L.; Springer, J.A.; Myers, R.C. (March 1995). "Comparison of the up-and-down, conventional LD50, and fixed-dose acute toxicity procedures". Food and Chemical Toxicology. 33 (3): 223–231. doi:10.1016/0278-6915(94)00136-c. PMID7896233.
^Lichtman, Aron H (August 1998). "The up-and-down method substantially reduces the number of animals required to determine antinociceptive ED50 values". Journal of Pharmacological and Toxicological Methods. 40 (2): 81–85. doi:10.1016/s1056-8719(98)00041-0. PMID10100496.
^Bruce, R (February 1985). "An up-and-down procedure for acute toxicity testing". Fundamental and Applied Toxicology. 5 (1): 151–157. doi:10.1016/0272-0590(85)90059-4. PMID3987991.
Dixon, W. J. (1965). "The Up-and-Down Method for Small Samples". Journal of the American Statistical Association. 60 (312): 967–978. doi:10.1080/01621459.1965.10480843. JSTOR2283398.
Brownlee, K. A.; Hodges, J. L.; Rosenblatt, Murray (1953). "The Up-and-Down Method with Small Samples". Journal of the American Statistical Association. 48 (262): 262–277. doi:10.1080/01621459.1953.10483472. JSTOR2281287.
