Side-by-side · Research reference
SelankvsThymalin
Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.
AHuman-MechanisticDraft11/40 cited
BHuman-MechanisticDraft12/40 cited
Selank
Anxiolytic + Cognitive · Russian Pharma
Intranasal · 2–3×/day during stress / cognitive demand
Thymalin
Immune restorer · Russian peptide bioregulator
IM · Daily for 5–10 days · 1-2×/year
01Mechanism of Action
Parameter
Selank
Thymalin
Primary target
Monoamine system (serotonin / GABA modulation) + immunomodulation via tuftsin domainZaderej 2014
T-cell precursors + thymus-axis maturation pathwayKhavinson 2002
Pathway
Tuftsin-derived immune signaling + CNS monoamine modulation → reduced anxiety + improved mood / cognitionMedvedev 2007
Modulation of T-cell differentiation + thymic hormone restoration in age-involuted thymusKhavinson 2002
Downstream effect
Anxiolytic + cognitive enhancement; immunomodulation via increased IL-6 + IFN-γMedvedev 2007Zaderej 2014
Restored T-cell populations, improved immune surveillance, reduced infection rates in elderlyKhavinson 2002
Origin
Synthetic 7-AA peptide derived from human tuftsin (immune-system tetrapeptide)Zaderej 2014
Polypeptide fraction isolated from calf thymus extractKhavinson 2002
Antibody development
—
—
02Dosage Protocols
Parameter
Selank
Thymalin
Frequency
2–3× per day during stress
Once daily during cycle
Lower / starter dose
75 mcg / dose
2.5 mg / day
Evidence basis
Human-mechanistic + Russian clinical trialsMedvedev 2007
Russian clinical + in vitroKhavinson 2002
Duration
10–14 day cycles, repeated as needed
5–10 day cycles, 1–2× per year
Reconstitution
Pre-formulated nasal spray (commercial); research vial: bacteriostatic water
Saline or bacteriostatic water
Timing
Morning + early afternoon preferred
Morning preferred
Half-life
Short (minutes plasma); CNS effect lasts ~3 hr
Hours (estimated)
04Side Effects & Safety
Parameter
Selank
Thymalin
Nasal irritation
Mild burning or congestion (transient)
—
Cognitive impairment
None — opposite effect (enhancement)
—
Allergic reaction
Rare hypersensitivity
Rare hypersensitivity to bovine-derived polypeptide
Long-term safety
Limited Western RCT data
Limited Western data
Pregnancy / OB
Avoid — insufficient data
Avoid
Injection site reaction
—
Mild erythema at IM site
Autoimmune flare
—
Theoretical risk in active autoimmune disease
Absolute Contraindications
Selank
- ·Pregnancy / breastfeeding
- ·Hypersensitivity to peptide
Thymalin
- ·Pregnancy / breastfeeding
- ·Bovine protein hypersensitivity
Relative Contraindications
Selank
- ·Active autoimmune disease (theoretical via immunomodulation)
Thymalin
- ·Active autoimmune disease
- ·Concurrent immunosuppressant therapy
05Administration Protocol
Parameter
Selank
Thymalin
1. Form
Pre-formulated nasal spray (commercial) or research vial reconstituted with bacteriostatic water.
Add 1–2 mL saline or bacteriostatic water per 10 mg vial.
2. Administration
Intranasal — 1–3 sprays per nostril per dose. Tilt head slightly back.
Intramuscular — deltoid or gluteal. Rotate sites.
3. Timing
Morning + early afternoon for cognitive demand; PRN for acute anxiety.
Morning preferred during cycle.
4. Storage
Refrigerate after reconstitution; ≤30 days. Light-protected.
Lyophilised: refrigerate, light-protected. Reconstituted: use immediately.
5. Caveat
Avoid co-administration with strong sedatives or other anxiolytics initially.
23–25G, 25–38 mm IM needle.
06Stack Synergy
Selank
— no documented stacks
Thymalin
+ Thymosin α-1
ModerateThymalin is a polypeptide complex; Thymosin α-1 is a single purified peptide. Both target the thymus-axis but at different levels — Thymalin restores broad thymic signaling; Tα-1 provides a specific molecular activator. Anecdotally combined for elderly immune support.
- Thymalin
- 5–10 mg IM · daily × 7 days
- Thymosin α-1
- 1.6 mg SQ · 2× weekly during the cycle
- Primary benefit
- Broad thymic restoration + targeted immune activation