It is possible that
bupropion (Wellbutrin) may cause your symptoms of tremors and joint pain. Please contact your provider and pharmacist to report the adverse effects and have them confirm by conducting a complete medication review, including prescription, over-the-counter, and any dietary and herbal supplements.
Some of the common side effects of bupropion are headaches (26%, compare to 23% of placebo), dry mouth (17%, compare to 7% of placebo), insomnia (11%, compare to 6% of placebo).