Cerebrolysin vs Dihexa
A neutral, side-by-side comparison of two nootropic & cognitive peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
Cerebrolysin
Cerebrolysin is a brain-derived peptide mixture produced by controlled enzymatic breakdown of porcine brain proteins. Unlike synthetic peptides, it is a complex of ~25% low-molecular-weight neuropeptides and ~75% free amino acids, with the bioactive peptide fraction mimicking the endogenous neurotrophic factors BDNF, NGF, GDNF, and CNTF in their mechanisms. It has a 30+ year clinical history in Eastern Europe and Asia for stroke recovery, traumatic brain injury, Alzheimer's disease, and vascular dementia — with a substantial human trial database.
Full profileDihexa
Dihexa is a synthetic hexapeptide derived from angiotensin IV, developed at Washington State University. It is considered one of the most potent nootropic peptides known — in rodent models it outperforms BDNF itself for synaptogenesis and cognitive enhancement, acting through the hepatocyte growth factor (HGF) / c-Met receptor system. Unlike most nootropics, Dihexa is highly lipophilic and can be administered transdermally or orally.
Full profile| Cerebrolysin | Dihexa | |
|---|---|---|
| Category | Nootropic & Cognitive | Nootropic & Cognitive |
| Also known as | FPF 1070, EBEWE Cerebrolysin, Brain-derived peptide mixture | PNB-0408, N-hexanoic-Tyr-Ile-(6) aminohexanoic amide |
| Evidence | Research-stage | Preclinical only |
| Dosing range | 5mL–30mL mL, Daily for 10–20 day courses (IV preferred in clinical use); SQ/IM for research access | 10mg–20mg mg, Once daily (or every other day — long-lasting effects) |
| Administration | Intravenous infusion (clinical standard — dilute in 100mL saline over 15–30 min), Intramuscular injection (research use — lower bioavailability), Subcutaneous injection (less common) | Oral (capsule), Transdermal (cream/lotion — lipophilicity makes this effective), Subcutaneous injection (less common) |
| Key side effects | Injection site pain (IM route), Hyperthermia / fever (rare, higher doses), Agitation or anxiety (uncommon), Nausea | Potential for pro-proliferative effects — HGF/c-Met pathway promotes cell growth (theoretical cancer concern at high doses), Headache (uncommon), Mental fatigue if overdosed, Long half-life means effects accumulate — take every other day initially |
| Cited sources | 3 references | 2 references |
Key differences
- Evidence level differs: Cerebrolysin is research-stage, while Dihexa is preclinical only.
- Administration: Cerebrolysin — Intravenous infusion (clinical standard — dilute in 100mL saline over 15–30 min), Intramuscular injection (research use — lower bioavailability), Subcutaneous injection (less common); Dihexa — Oral (capsule), Transdermal (cream/lotion — lipophilicity makes this effective), Subcutaneous injection (less common).
- Dosing units differ: Cerebrolysin is dosed in mL, Dihexa in mg — they operate at different scales.
- Frequency: Cerebrolysin is typically Daily for 10–20 day courses (IV preferred in clinical use); SQ/IM for research access; Dihexa is Once daily (or every other day — long-lasting effects).
- Research depth: this profile cites 3 sources for Cerebrolysin vs 2 for Dihexa.
How each works
Cerebrolysin
Cerebrolysin's neuroprotective effects have been demonstrated in over 100 clinical trials, though most are from Eastern European and Asian centers with varying methodological quality. The CACTUS trial (N=256, multicenter) showed significant improvement in cognitive outcomes after ischemic stroke vs placebo. The ARTIST trials evaluated Cerebrolysin for Alzheimer's disease with mixed results. Meta-analyses of stroke and dementia trials generally support modest-to-moderate benefit. Mechanistically, the peptide fraction upregulates BDNF/NGF signaling, reduces excitotoxicity, inhibits caspase-3, and promotes synaptogenesis in animal and in vitro models.
Dihexa
Dihexa (PNB-0408) was developed by Joseph Harding and colleagues at WSU as a metabolically stable angiotensin IV analog. It binds hepatocyte growth factor (HGF), potentiating its interaction with the c-Met receptor — a pathway critical for dendritic branching, synapse formation, and synaptic plasticity. In rodent Alzheimer's and scopolamine-impaired models, Dihexa restored cognitive performance at doses ~7 orders of magnitude lower than BDNF. It readily crosses the blood-brain barrier due to its lipophilicity, unlike BDNF itself.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.