the potential to cause nephro- and hepatotoxicity. This is variable among species. Cats, in particular, are sensitive to the NSAIDs. Acetaminophen is contraindicated is cats due to risk of methemoglobinemia. In general, by mixing anesthetic and analgesic drugs, the dose required for each individual drug is reduced, sometimes quite dramatically. Start at the low end of the dose range listed; you can always give more if needed!  Drugs not listed below can be mixed using the same concepts, mix a sedative or hypnotic with an analgesic. Do not mix drugs in the syringe until you have determined that they are compatible when mixed. If in doubt administer separately. Determining expiration dates for mixed/diluted anesthetic or pain relieving drugs: In the absence of empirical evidence, expiration dates of diluted or mixed drugs will be determined as follows: Manufacturer?s dating of the drugs to be mixed together will determine the expiration date if shorter than the timelines given below. Avertin - All solutions should be discarded 4 months after mixing, including stock solutions. pH should be tested prior to every use. Solution should only be used if pH is greater than 5. See http://www.ahc.umn.edu/rar/avertin.html Any substance which shows signs of precipitation, change of color, change in transparency or other signs of transformation should be immediately discarded. All diluted/ mixed substances must be combined into sterile containers (unless the combination is for a single acute procedure and the mixture will not be stored). Ketamine/Diazepam : Mix drugs 1:1 by volume and administer 0.1