Somatostatin, which will be upregulated in response to exogenous
GH to inhibit endogenous
GH, also has been implicated in being responsible, in part, for some of the downregulation of thyroid hormones. Mallet on anabolicreview.com has made some excellent posts recently about monitoring your core temp....this can be indicative of decreased (or increased) thyroid function. This may be the best strategy (next to bloodwork) to gauge if and how much
GH is affecting your thyroid function over time. If you're taking
GH for its anabolic properties, I'd only take T3 on an "as needed" basis. If you're taking
GH for it's fat buring potential, supplementing with T3 could be very beneficial.