I've been taking cymbalta 120mg/day for years. It's now very expensive. Is generic Effexor (venlafaxine) an alternative especially for the chronic shoulder pain?

Effexor (venlafaxine) Yes Effexor (venlafaxine) shares many of the same properties as Cymbalta and is much cheaper. Discuss with your doctor who will likely be willing to try it. You have to slowly go up icon the dosing, so don't give up too early if not helping on the starter dose. Your doctor can help you set up a dosing sequence tailor made for you.
Yes/No ?maybe. Effexor is a member of the same family as Cymbalta but it is not fda approved for the chronic pain. It could help with this but the Cymbalta appears to affect the pain sensors more than effexor. This doesnt mean it wont work. I have many pts who report benefits to the pain as well. If you are taking this for fibromyalgia- then Lyrica or savella (milnacipran) may also be of benefit.