ME/CFS (myalgic encephalomyelitis)
Myalgic encephalomyelitis / chronic fatigue syndrome — a complex multi-system illness defined by post-exertional malaise (PEM), unrefreshing sleep, cognitive impairment, and orthostatic intolerance.
What changes during this transition
ME/CFS is defined by the IOM 2015 / NAM criteria: substantial reduction in pre-illness activity persisting >6 months + PEM + unrefreshing sleep + either cognitive impairment or orthostatic intolerance. Roughly half of post-acute COVID (PASC) patients also meet ME/CFS criteria (Davis 2023), and the post-viral-onset phenotype overlaps mechanistically with PASC. Standard-of-care is PACING (NOT graded exercise — the PACE-trial framework was retracted as harmful for this population), heart-rate-ceiling protocols (Workwell), orthostatic-intolerance management, sleep optimization, and triad-overlap screening (MCAS, POTS, EDS). Peptide relevance here is heavily caveat-loaded. There is no peptide with ME/CFS-specific approval anywhere globally. The substrate clusters around component-symptom rationale: Selank for the anxiety + cognitive-fog overlay (Russian clinical lineage, benzo-sparing case), B12-methylcobalamin for the well-documented functional B12 deficiency subset (Regland 2015 Swedish cohort), KPV for the MCAS-overlap subset, and MOTS-c as a BIOMARKER candidate (Peluso 2023 found it reduced in post-viral neuropsychiatric PASC) rather than a validated therapeutic. The overarching editorial frame: pacing is the precondition, peptides are layered adjuncts at best, and any peptide that 'feels like it expands the energy envelope' is the most dangerous kind because it invites the user past their actual ceiling and into a PEM crash.
Important caveat
PACING IS NON-NEGOTIABLE. No peptide here addresses PEM biology. Anything that produces a subjective energy lift is a trigger for the failure mode where users push past their real ceiling and crash. ME/CFS specialty-clinic involvement matters more than peptide selection. Post-viral-onset users should be screened for the triad overlap (MCAS, POTS, EDS) — the relevant peptide picks change substantially if any of those are co-present.
Peptides editorially relevant to me/cfs (myalgic encephalomyelitis)
4 peptides from the library — each evidence-tiered honestly.
- SelankTier 3
Synthetic tuftsin analog (heptapeptide)
Russian-developed anxiolytic/nootropic peptide. Most clinical data is in Russian and methodologically thin by Western standards. Tier 3. Routes include intranasal — a natural pair with Juno's nasal-spray prep guide.
- B12 (Methylcobalamin)Tier 1
Vitamin (methylcobalamin)
Vitamin B12 in the methyl form. Solid evidence for treating documented deficiency and pernicious anemia. The wellness-clinic 'energy injection' market for non-deficient adults has no clinical-trial support.
- KPVTier 3
α-MSH C-terminal tripeptide
Short tripeptide fragment of a natural hormone (alpha-MSH). Appears to carry the anti-inflammatory signaling of the parent hormone without its pigmentation effects. Growing animal and early-human work, especially for inflammatory bowel disease.
- MOTS-cTier 3
Mitochondrial-derived peptide
Mitochondrial-encoded peptide with strong rodent data on insulin sensitivity, endurance, and metabolic health.
Want this list to grow? The library is editorial — if there’s a peptide you think belongs on this page with documented or mechanistically-clear evidence, send us a note with the citation and we’ll review it under the same evidence-tier discipline as every other entry.