In this case series, the occurrence and successful treatment of anaphylaxis after the intravenousadministration of amoxicillin/clavulanic acid are described in two dogs under generalanesthesia. Within five to ten minutes after the administration of the antibiotic, a severe hypotensionoccurred in both dogs, accompanied by labial and periorbital swelling and erythema.Therapy consisted of counteracting the cardiovascular effects of anaphylaxis and preventingfurther release of inflammatory mediators. Both dogs recovered uneventfully from the drugrelatedanaphylaxis.