While a veterinarian should be consulted before embarking on a course of medication for a dog, aspirin can be appropriate for dogs in some cases, reports Vetinfo. Dosage recommendations usually fall within the range of 5 to 15 milligrams per pound every 12 hours.
The side effects for aspirin are generally the same for dogs as they are for people. An overdose can cause renal failure. Long-term use can cause gastrointestinal problems and ulcers, and even short-term, responsible use of aspirin may cause an increase in the amount of time it takes for cuts to form clots, according to Vetstreet. Pain medications made specifically for dogs are available, reports WebMD.