While ibuprofen is not deadly to dogs, it creates adverse gastrointestinal side effects and its administration is not recommended for canines, according to WebMD. Ibuprofen is an analgesic medication, and other medications in its class are safer for dog administration.
Aspirin is recommended for dogs expressly for the treatment of arthritis. Aspirin is an analgesic which falls under the NSAID category of drugs. NSAID stands for non-steroidal anti-inflammatory. Aspirin has a much lower incidence of negative stomach side effects in dogs when compared to ibuprofen. Another medication not recommended for dogs is the medicine Butazolidin, which is often administered to horses for pain.