This article is from the Pet Owner's Guide to Common Small Animal Poisons, by Julie Dahlke, DVM, a graduate of the University of Minnesota, College of Veterinary Medicine.
The pain relievers discussed here are known as NSAID's (non-steroidal
anti-inflammatory drugs) and are widely prescribed with caution by
veterinarians to relieve pain from arthritis and other
conditions. Animal dosages, however, are much lower than human
dosages. Use of NSAID's can significantly increase the risk for
development of stomach or intestinal ulcers, particularly in a sick
patient, or one receiving other medications. These pain relievers
cause signs of poisoning by decreasing the mucous production in the
stomach. Mucous serves to protect the stomach from the acids it
secretes and reduction in mucous production decreases the protection
the stomach has from acid secretion and increases the likelihood of
ulcer formation. In addition these drugs indirectly decrease the blood
flow to vital organs, particularly the kidney, and can result in
significant kidney damage. Two regular strength aspirin in a small dog
can cause clinical signs of poisoning. As with Tylenol, cats are more
sensitive to these drugs and should never be given these medications
unless under the specific direction of a veterinarian.
Again, these drugs can be safely used and, in fact, are employed in
veterinary practice every day in appropriate doses and after careful
medical evaluation of the patient. The important point is to recognize
that dogs and cats do not respond in the same way to human medications
that people do. Any medications need to be discussed with and
prescribed by a veterinarian prior to giving them to your pet to avoid
an inadvertent and tragic poisoning.
 
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