Understand the source comparison
Peptides for Long COVID Brain Fog: Clinical Comparison
Semax BDNF upregulation, neurotropic signaling Neuroinflammation → hippocampal/prefrontal dysfunction Human RCTs, 70%+ response rate 3–5 days subjective, 10–14 days objective 0.1% intranasal, 300–600 mcg twice daily, 10–21 days Constant cognitive dullness, mem
No winner is assigned.
This page preserves a source comparison for education. It does not add a rating, recommendation or clinical judgment.
- Semax
- BDNF upregulation, neurotropic signaling
- Neuroinflammation → hippocampal/prefrontal dysfunction
- Human RCTs, 70%+ response rate
- 3–5 days subjective, 10–14 days objective
- 0.1% intranasal, 300–600 mcg twice daily, 10–21 days
- Constant cognitive dullness, memory lapses, slowed processing. Worse with mental exertion, not stress-dependent
- Selank
- GABAergic potentiation, cortisol modulation
- Stress axis dysregulation → anxiety-amplified fog
- Human RCTs, 50–68% subjective improvement
- 24–48 hours
- 0.15% intranasal, 600–900 mcg 1–2× daily, 14–28 days
- Brain fog worsens with stress/anxiety, improves with distraction, correlates with hypervigilance or panic symptoms
- BPC-157
- VEGF receptor activation, angiogenesis, endothelial repair
- Vascular dysfunction → cerebral hypoperfusion
- Preclinical models, case series only. No RCTs
- 4–6 weeks gradual
- 250–500 mcg subcutaneous 1–2× daily, 30+ days
- Brain fog with orthostatic component, documented hypoperfusion on imaging, failed neuroinflammatory therapy
- Cerebrolysin
- Neurotrophic peptide mixture (BDNF, NGF, CNTF analogues)
- Neuroinflammation + neurodegeneration
- Human trials in stroke/TBI, no long COVID-specific data
- 7–14 days
- 10–30 mL IV infusion, 10–20 sessions
- Severe persistent cognitive impairment, consideration after single-agent failure
- Dihexa
- HGF/Met pathway activation
- Synaptogenesis, dendritic spine density
- Preclinical only. No human safety data
- Unknown in humans
- Experimental. Not recommended outside research settings
- Not clinically available
- Professional Assessment
- Semax has the strongest evidence base for post-viral neuroinflammatory brain fog with documented BDNF restoration and 70%+ response in human trials. Selank addresses a different mechanism (stress amplification) and works for roughly half of patients whose fog is anxiety-linked. BPC-157 is mechanistically rational for vascular cases but lacks controlled human data. It's second-line after inflammation-targeted therapy. The table clarifies: choosing correctly depends on identifying your dominant pathway, not matching symptom checklists.