Carry 9-12 tablets of Ibuprofen and several Tums in a zip lock bag inside your "manly" saddlebag. At the first sign of knee pain take 600mg of Ibuprofen (3 tabs) with something to eat. Not only will the pain subside but the anti-inflammatory effect will reduce swelling of the joint as well.
The Tums help in warding off muscle cramps. I can't cite any medical journals as references but I think it's the calcium. I have helped many friends with this simple kit. (Gatorade and bananas have plenty of potasium but no Calcium.)
Also carry a spoke wrench in same saddle bag and tape extra spoke inside your seat post (and tool to remove said seat post)
A dollar bill work well as a boot for a cut tire.
Gerry