Elevated alt levels for a year and a half. all hepatitis tests negative. can injecting humira (adalimumab) cause elevated levels? can injection into muscle cause?

Yes: Skeletal muscle does contain ast and alt and really heavy-duty intramuscular injections can raise these values. Timing the lab draws might help rule this in or out. I trust that screens for hemochromatosis and wilson's also showed you are not affected; the metabolic syndrome may also raise these. I'm glad you're taking a proactive role toward your health & i wish you luck.