Tennis elbow is nothing to do with the joint - it is an overuse injurywhich affects the small muscles around the ulnar border of the upper forearm.
To fix it you need to cease the activity that aggravates it, and begin to do rehab exercises - generally speaking it is strengthening of the entensors and flexors of the forearm, the powerball rehab tool is invaluable in rehabing this injury.
Some deep tissue manipulation and hot/cold frictions and compresses would not go amiss either.
Dunno what to tell you if you have tennis elbow, but in my experience, its best if you take a glucosamine and chondroitin supplement if your going to take Havoc/Epistane. It would also be a good idea to take fish oil and flaxseed oil 2x a day. Or you could just take the fish oil, but I like taking both…for good measure.
BTW, I’ve run Havoc once and Epistane twice and anything less than that absolutely KILLED my joints…especially my knees and elbows.