APPENDIX B DRUG FORMULARY 783
Ketamine (Ketalar,Ketavet, Vetalar)Anesthetic agent. NMDAreceptor antagonist. Exactmechanism of action isnot known, but appearsto act as dissociativeagent. Rapidlymetabolized andeliminated in mostanimals.Causes pain with IMinjection. Tremors,spasticity, and convulsiveseizures have beenreported. Increases cardiacoutput compared to otheranesthetic agents. Do notuse in animals with headinjury because it mayelevate CSF pressure.Oftenusedincombination with otheranesthetics and anestheticadjuncts, such as xylazine,acepromazine, ordiazepam. IV dosesgenerally less than IMdoses.100 mg/mL injectionsolution.
Dog: 5.5–22 mg/kg IV, IM(recommend adjunctivesedative or tranquilizertreatment).Cat: 2–25 mg/kg IV, IM(recommend adjunctivesedative or tranquilizertreatment).Dog and cat: Dose forconstant rate infusion:0.5 mg/kg IV followed by 10
μg/kg/min. May be
used in combination withother analgesics.Ketoconazole (Nizoral)Azole (imidazole)antifungal drug. Similarmechanism of action asother azole antifungalagents. Inhibits ergosterolsynthesis in fungal cellmembrane. Fungistatic.Efficacious againstdermatophytes andvariety of systemic fungi,such asHistoplasma,
Blastomyces,andCoccidioides. Also active
againstMalassezia.
Adverse effects in animalsinclude dose-relatedvomiting, diarrhea, andhepatic injury. Enzymeelevations are common.Do not administer topregnant animals.Ketoconazole causesendocrine abnormalities,most specifically inhibitionof cortisol synthesis.Druginteractions:
Ketoconazole will inhibitmetabolism of otherdrugs (anticonvulsants,cyclosporine, cisapride).Oral absorption dependson acidity in stomach. Donot administer withantisecretory drugs orantacids. Because ofendocrine effects,ketoconazole has beenused for short-termtreatment ofhyperadrenocorticism.200 mg tablets;100 mg/mL oralsuspension (onlyavailable inCanada).Dog: 10–15 mg/kgq8–12h po. ForMalassezia canisinfection:5 mg/kg q24h po. Forhyperadrenocorticism:15 mg/kg q12h po.Cat: 5–10 mg/kg q8–12hpo.(continued)