Animal Dose Converter

The FDA guidance (Section V.B–C) recommends against mg/m² scaling for:

• drugs given topically, intranasally, subcutaneously or intramuscularly whose dose is limited by local toxicity — normalise to concentration or amount at the site instead;
• drugs given into a compartment with little distribution outside it (intrathecal, intravesical, intraocular, intrapleural);
• proteins over 100 kDa given intravascularly — normalise to mg/kg.

It also describes when mg/kg scaling may be justified, e.g. when NOAELs occur at a similar mg/kg dose across species. The Km factors assume each species' typical weight (Table 1 working range); for an animal outside that range, use the allometric method with its actual weight.

• U.S. FDA, CDER. Guidance for Industry: Estimating the Maximum Safe Starting Dose in Initial Clinical Trials for Therapeutics in Adult Healthy Volunteers. July 2005. Table 1 (Km factors), Appendix C (allometric derivation), Section VII (safety factor). FDA guidance page.
• Nair AB, Jacob S. A simple practice guide for dose conversion between animals and human. J Basic Clin Pharm. 2016;7(2):27–31. PMID 27057123. (AED naming; secondary summary of the FDA method.)
• Reagan-Shaw S, Nihal M, Ahmad N. Dose translation from animal to human studies revisited. FASEB J. 2008;22(3):659–661. PMID 17942826. (Secondary restatement of the FDA formula.)
• Freireich EJ, Gehan EA, Rall DP, Schmidt LH, Skipper HE. Quantitative comparison of toxicity of anticancer agents in mouse, rat, hamster, dog, monkey, and man. Cancer Chemother Rep. 1966;50(4):219–244. PMID 4957125. (Cross-species toxicity data behind the body-surface-area approach.)
• Not implemented here: pharmacokinetic approaches based on interspecies scaling of clearance (Mahmood et al., J Clin Pharmacol 2003;43:692–697; Reigner & Blesch, Eur J Clin Pharmacol 2002;57:835–845), which the FDA guidance names as alternatives.