Good Afternoon Rick and welcome! I am Dr. Loretta, a licensed veterinarian and I am happy to answer your question.
These discs contain a large amount of aspirin which can cause stomach ulcers in dogs. If this was within 2 hrs of ingestion, induce vomiting by following these instructions:
Give 1 teaspoons of peroxide per 5 pounds of weight and wait 15 minutes. If no vomiting, then try it again. You can do this 3 times safely.
If this has been longer, your guys is at risk for an ulcer which can cause devastating digestive issues for your guy, since he is older. I would recommend, to be safe, Rick, that you take your guy to your vet for observations. Any vomiting or anorexia will show there is a problem.
Does that make sense to you?
Please let me know if you have ANY other questions. My goal is to give you 100% satisfaction and if you are not yet satisfied, please REPLY so I can clarify for you.
Sincerely, ***** *****