Thymosin Beta-4 vs Urocortin
The body's natural healing peptide that accelerates tissue repair and reduces inflammation
A powerful stress-response peptide that protects your heart and helps your body handle pressure
Written by Michael Carroll — Owner, Director of Research · Reviewed by the Peptide Initiative Research Team · Editorial standards
Quick comparison
Dose range
Thymosin Beta-4
2–5 mg
Urocortin
36–360 pmol/min
Frequency
Thymosin Beta-4
Twice weekly
Urocortin
Once daily
Administration
Thymosin Beta-4
Subcutaneous injection
Urocortin
As directed by healthcare provider
Cycle length
Thymosin Beta-4
8-12 weeks
Urocortin
Ongoing/indefinite
Onset speed
Thymosin Beta-4
Moderate (1-2 weeks)
Urocortin
Moderate (1-2 weeks)
Evidence level
Thymosin Beta-4
Moderate human trials (Phase 1-2)
Urocortin
Moderate human trials (Phase 1-2)
Benefit ratings
Wound Healing
Inflammation Reduction
Tissue Regeneration
Cardiovascular Protection
Stress Response & Resilience
Heart Function Support
Compound specifications
Thymosin Beta-4
Molecular formula
C212H350N56O78S
Molecular weight
4963
Half-life
Dose-dependent (increases with higher doses)
Bioavailability
100% (subcutaneous and intravenous)
CAS number
77591-33-4
Urocortin
Molecular formula
C216H329N59O64S
Molecular weight
Approximately 4,700 Daltons
Half-life
Approximately 2-6 hours (varies by route of administration)
Bioavailability
Varies by route of administration
CAS number
173190-76-4
Dosing compared
Thymosin Beta-4
Subcutaneous injection
2-5 mg (community injectable practice for 'TB-500')
Once or twice weekly · 4-6 week loading phase, then weekly maintenance
Documented community/research-practice injectable dosing for tissue repair; thymosin beta-4 has ~100% bioavailability by the subcutaneous route [1]. Not an FDA-approved use.
Topical ophthalmic (eye drops)
0.1% (1 mg/mL) RGN-259 solution, 1 drop
Several times daily (e.g. up to 5x/day) · 4 weeks
0.1% RGN-259 ophthalmic solution used in phase III neurotrophic keratopathy and dry-eye trials, applied as eye drops several times daily for ~4 weeks [5].
Intravenous injection
450-1200 mg
IV push daily for the first 3 days, then weekly · Total of 7 doses over ~5 weeks
Doses studied in the RGN-352 acute myocardial infarction clinical program, given IV after PCI [6].
Urocortin
Intravenous infusion
5 ng/kg/min (urocortin-2)
Continuous infusion · 4 hours
Adjunct dose used in the UNICORN study of 53 acute decompensated heart failure patients [6]. Investigational only.
Urocortin-2 36–360 pmol/min or urocortin-3 1.2–12 nmol/min (ascending)
Incremental infusion · Per study protocol
Ascending IV doses studied in chronic heart failure patients; increased cardiac index and reduced vascular resistance [7]. Research use only — no approved product.
Best suited for
Thymosin Beta-4
Post-Surgery Recovery
Accelerates healing of surgical wounds and reduces post-operative inflammation and scarring
Chronic Wound Management
Helps pressure ulcers, venous stasis ulcers, and other slow-healing wounds progress faster
Tissue Regeneration
Supports repair of damaged tissues from injury, burns, or degenerative conditions
Urocortin
Supporting cardiovascular health during stressful periods
Urocortin is particularly well-suited for individuals focused on supporting cardiovascular health during stressful periods. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Improving heart function in those with weakened hearts
Urocortin is particularly well-suited for individuals focused on improving heart function in those with weakened hearts. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Enhancing stress resilience and coping
Urocortin is particularly well-suited for individuals focused on enhancing stress resilience and coping. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Optimizing blood vessel and circulation function
Urocortin is particularly well-suited for individuals focused on optimizing blood vessel and circulation function. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Side effects
Thymosin Beta-4
Common
- Injection site redness
- Injection site swelling
Uncommon
- Temporary mild headache
- Mild bruising at injection site
- Transient fatigue
Serious
- Allergic reaction
Urocortin
Common
- Facial flushing
- Mild headache
- Dizziness
- Injection site response
- Nausea
Serious
- Severe allergic reaction
- Severe blood pressure changes
- Heart palpitations
Safety & evidence
Thymosin Beta-4
Evidence level
Moderate human trials (Phase 1-2)
FDA status
Research compound
Safety overview
Thymosin Beta-4 is a naturally occurring peptide found in all cells and body fluids in the human body. Clinical trials have demonstrated excellent safety even at very high doses. IV studies showed doses up to 1260 mg were well tolerated with no serious adverse events.
Contraindications
- Active systemic infections
- Severe immunosuppression
- Hypersensitivity to thymosin or any component
- Pregnancy (insufficient safety data)
Urocortin
Evidence level
Moderate human trials (Phase 1-2)
FDA status
Research compound
Safety overview
Urocortin III (a corticotropin-releasing factor analogue) shows preclinical safety in animal models with potential CNS and cardiovascular effects through CRF receptor activation. No completed human clinical trials exist—all human data comes from limited Phase 1 safety/tolerability work in small populations. Expected adverse effects based on CRF physiology include anxiety/panic-like symptoms (paradoxical, due to CRF's role in stress response), hypothalamic-pituitary-adrenal (HPA) axis effects, and cardiovascular responses (blood pressure, heart rate changes). Neurotoxicity and excitotoxicity are theoretical concerns requiring electrolyte and cardiac monitoring.
Contraindications
- Hypersensitivity to urocortin or CRF-related peptides
- Severe hypertension without medical monitoring
- Acute coronary syndrome (heart attack) - requires careful evaluation
- Uncontrolled arrhythmias
- Pregnancy and breastfeeding (limited safety data)
Which is right for you?
Choose Thymosin Beta-4 if...
- Recovering from injuries or surgery
- Improving wound healing speed
- Reducing inflammation
- Minimizing scar formation
Choose Urocortin if...
- Supporting cardiovascular health during stressful periods
- Improving heart function in those with weakened hearts
- Enhancing stress resilience and coping
- Optimizing blood vessel and circulation function