What education would you provide when prescribing pain medication for this patient?

Order Instructions
A 78-year-old male patient comes to your office complaining of increased left knee pain for the past 3 to 4 months. He has had no history of recent injury. An x-ray done less than 4 months ago showed degenerative osteoarthritic changes. He has full range of motion and denies any recent swelling, pedal edema, or discoloration. He has been a long-distance runner for many years and was diagnosed with osteoarthritis of his left knee more than 10 years ago. He has decreased his weekly running, but the pain is persistent and is affecting his daily activities. He has been using over-the-counter NSAIDs on and off, but states they are no longer working and wants something “stronger.” His vital signs are all normal and he has no history of fever, chills, or rashes. He is otherwise healthy.
Which medications do you feel would be safe and appropriate for this patient’s chronic pain?
What education would you provide when prescribing pain medication for this patient?