HGH Fragment 176-191 vs P21
Side-by-side comparison of key properties, dosing, and research.
Fat Loss & Metabolic
HGH Fragment 176-191Cognitive EnhancementAnti-Aging & Longevity
P21- Summary
- HGH Fragment 176-191 (also known as AOD-9604) is a stabilized, modified fragment of the human growth hormone molecule corresponding to amino acids 176–191 with an addition of a tyrosine residue at the N-terminus. It retains HGH's fat-burning properties without the anabolic, diabetogenic, or IGF-1-stimulating effects.
- P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
- Half-Life
- ~30 minutes
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Admin Route
- SubQ
- SubQ, Intranasal
- Research
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- Typical Dose
- 250–500 mcg
- 100–500 mcg
- Frequency
- 1–3 times daily
- Once daily
- Key Benefits
- Selective fat burning without anabolic side effects
- Reduces visceral and subcutaneous fat
- No insulin resistance or blood glucose disruption
- Does not stimulate IGF-1
- May support cartilage and bone repair (at higher doses)
- No effect on growth or organ size
- Promotes hippocampal neurogenesis
- Enhances spatial memory and learning
- Increases BDNF expression
- Reduces amyloid-beta plaque formation (animal models)
- Anti-tau pathology potential
- Cognitive enhancement without stimulant effects
- Potential therapeutic for Alzheimer's and cognitive aging
- Side Effects
- Injection site irritation
- Temporary lethargy
- Headache (rare)
- Nausea (rare)
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Stacks With
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