I have hypothyroid and have been on synthroid (thyroxine) 112mcg test results are tpo high 173, tsh low 0.126, t4 free normal1.38, is there a need to change meds?

Hashimoto's: The elevated anti-TPO indicates hashimoto's thyroiditis, but you basically know that since you are hypothyroid. The low TSH may suggest that the dose of synthroid (thyroxine) is very slightly too high, even though the ft4 is normal, but if you are feeling well (no symptoms of hyper, not heart problems, bones ok) i might wait 3-6 months and check again.

Hypothyroid: Tpo antibodies do not change with treatment. They are indicators of the cause of your hypothyroidism - autoimmune thyroid disease aka grave's disease. Your TSH is slightly suppressed meaning you are getting too much synthroid (thyroxine). Long term side effects of too much synthroid (thyroxine) include an increased predilection for osteoporosis and atrial fibrillation, therefore a slight reduction in dose is warranted.