AOD-9604 vs HGH Fragment 176-191

Verdict: These are near-twins: both are the lipolytic tail (176-191 region) of the growth hormone molecule, isolated so fat metabolism comes without GH's growth or glucose effects. AOD-9604 is Fragment 176-191 plus one added tyrosine for stability — and it's the only one of the pair with a human trial history (obesity trials in the 2000s, which showed modest results and were shelved commercially). Practical differences are small; AOD's oral/injectable flexibility and trial data give it the slight edge in credibility, while plain Frag is typically cheaper.

Side by side

AOD-9604HGH Fragment 176-191
Typical dose250 mcg–500 mcg250 mcg–500 mcg
Frequencydaily, often fasted1–2x daily, fasted
Administrationsubcutaneous injectionsubcutaneous injection
Common vials2 mg, 5 mg2 mg, 5 mg
Typical mix5 mg + 2 ml water5 mg + 2 ml water
Units for typical dose12 units (300 mcg)10 units (250 mcg)

What the trials actually showed

AOD-9604's phase 2 obesity trials found statistically significant but modest weight loss versus placebo — real signal, underwhelming magnitude, which is why it never became a drug. That result is worth internalizing: these fragments are studied as metabolic assistants, not GLP-1-scale interventions. Anyone selling them as such is selling.

Timing is the protocol

Both are dosed 250–500 mcg daily in a fasted state — most commonly on waking, ideally before fasted cardio — because insulin blunts the lipolytic mechanism. Taking either alongside a meal is the classic way to pay for a peptide and receive nothing.

Stability and handling

The added tyrosine makes AOD-9604 meaningfully more stable in solution; plain Fragment 176-191 is one of the more fragile peptides in circulation and rewards careful cold-chain handling, gentle reconstitution and shorter post-mix windows (2–4 weeks refrigerated).

Can you stack them?

Pick one, not both — identical mechanism. Either appears alongside GH secretagogues in recomposition stacks, or standalone for fasted-cardio protocols.

More comparisons

Educational comparison based on commonly published research protocols — not medical advice or an endorsement of any compound.