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Peptide Database

Goals
Fat LossMuscle BuildingInjury HealingAnti-AgingCognitive EnhancementSleep OptimizationImmune SupportGut HealingSkin RejuvenationSexual Health
Peptides
Adipotide
Weight Management
AOD-9604
Weight Management
BPC-157
Healing & Recovery
Cagrilintide
Weight Management
CJC-1295
Growth Hormone
DSIP
Sleep & Recovery
Epithalon
Anti-Aging
GHK-Cu
Anti-Aging
GHRP-2
Growth Hormone
HCG
Hormone Support
Hexarelin
Growth Hormone
HGH
Growth Hormone
IGF-1 LR3
Growth Hormone
Kisspeptin
Hormone Support
Melanotan-2
Cosmetic
MOTS-C
Metabolic
NAD+
Anti-Aging
Oxytocin Acetate
Hormone Support
PEG-MGF
Recovery
PNC-27
Cancer Research
PT-141
Sexual Health
Retatrutide
Weight Management
Selank
Cognitive
Semaglutide
Weight Management
Semax
Cognitive
Sermorelin
Growth Hormone
Snap-8
Cosmetic
SS-31
Mitochondrial
TB-500
Healing & Recovery
Tesamorelin
Growth Hormone
Thymosin Alpha-1
Immune
Tirzepatide
Weight Management
Total Peptides: 32
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Peptide Comparison

Substance P AntagonistsvsTB-500

NK1 receptor blockers that reduce pain signals and nausea at the source

A powerful fragment of thymosin beta-4 that acts like your body's repair signal—speeding up healing of muscles, tendons, and tissues by promoting cell migration and new blood vessel growth right where you need it most.

Healing & RecoveryHealing & Recovery

At a Glance

Quick
comparison

Dose Range

Substance P Antagonists

80 mg–125 mg mg

TB-500

2–5 mg

Frequency

Substance P Antagonists

Once daily

TB-500

Twice weekly

Administration

Substance P Antagonists

Oral capsule

TB-500

Subcutaneous injection

Cycle Length

Substance P Antagonists

Ongoing/indefinite

TB-500

4-6 weeks

Onset Speed

Substance P Antagonists

Moderate (1-2 weeks)

TB-500

Moderate (1-2 weeks)

Evidence Level

Substance P Antagonists

Moderate human trials (Phase 1-2)

TB-500

Moderate human trials (Phase 1-2)

Efficacy

Benefit
ratings

Substance P Antagonists
TB-500

Anti-Nausea & Antiemetic

Substance P Antagonists95%
TB-5000%

Pain Modulation

Substance P Antagonists75%
TB-5000%

Neuroprotection

Substance P Antagonists70%
TB-5000%

Healing Speed

Substance P Antagonists0%
TB-50095%

Tissue Repair

Substance P Antagonists0%
TB-50093%

Anti-Scarring

Substance P Antagonists0%
TB-50088%

Technical Data

Compound
specifications

Substance P Antagonists

Molecular Formula

C23H21F7N4O3

Molecular Weight

534.4 g/mol

Half-Life

9-13 hours (elimination half-life)

Bioavailability

Approximately 60-65% oral bioavailability; food may increase absorption

CAS Number

170729-80-3

TB-500

Molecular Formula

C38H68N10O14

Molecular Weight

889.01 g/mol

Half-Life

2-3 days (systemic)

Bioavailability

High via subcutaneous injection (~100%)

CAS Number

885340-08-9

Protocols

Dosing
tiers

Substance P Antagonists

TB-500

starting

2-2.5 mg

Twice weekly

4-6 weeks

Start here to assess your tolerance and response. Many people see good results at this dose. Split your weekly dose into two injections spaced 3-4 days apart (like Monday and Thursday).

standard

4-5 mg

Twice weekly (split into 2-2.5 mg doses)

4-6 weeks

The most commonly used protocol for moderate injuries. Your total weekly dose is 4-5 mg, split into two injections. This is the sweet spot where most users see significant healing benefits.

advanced

5-10 mg

Twice weekly (2.5-5 mg per injection)

4-8 weeks

Higher doses for severe or stubborn injuries. Some protocols use a loading phase of higher doses for 1-2 weeks, then drop to maintenance. Work with a provider for doses above 5 mg weekly.

Applications

Best
suited for

Substance P Antagonists

Managing severe nausea from cancer treatments

Substance P Antagonists is particularly well-suited for individuals focused on managing severe nausea from cancer treatments. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Chronic pain reduction

Substance P Antagonists is particularly well-suited for individuals focused on chronic pain reduction. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

Improving quality of life during intensive medical therapy

Substance P Antagonists is particularly well-suited for individuals focused on improving quality of life during intensive medical therapy. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.

TB-500

Athletes Recovering from Muscle Injuries

If you've pulled a hamstring, strained your back, or torn a muscle, TB-500 helps accelerate the healing process by promoting cell migration to the injury site and supporting new blood vessel growth. It's especially useful for injuries that just won't seem to fully heal.

Tendon and Ligament Problems

Tendons and ligaments are notoriously slow healers because they have poor blood supply. TB-500 promotes angiogenesis (new blood vessel formation) and helps repair these stubborn connective tissue injuries—think Achilles tendonitis, tennis elbow, or rotator cuff issues.

Post-Surgical Recovery

After surgery, your body needs to repair a lot of tissue quickly. TB-500 supports wound healing, reduces inflammation, and may help minimize scar tissue formation. Some protocols use it alongside traditional recovery to potentially speed up the healing timeline.

Chronic Inflammation and Slow Healers

Some people just heal slowly—whether due to age, diabetes, or other factors. TB-500 helps regulate the inflammatory response and promotes the cellular processes needed for tissue repair. It essentially tells your body to focus healing resources where they're needed most.

Safety Profile

Side
effects

Substance P Antagonists

Common

  • Headache
  • Fatigue or weakness
  • Constipation

Uncommon

  • Loss of appetite
  • Dizziness

Serious

  • Stevens-Johnson Syndrome (SJS)

TB-500

Common

  • Injection site redness
  • Mild fatigue or lethargy
  • Mild headache
  • Slight flushing

Uncommon

  • Head rush or lightheadedness
  • Temporary nausea

Serious

  • Allergic reaction

Research Status

Safety
& evidence

Substance P Antagonists

Evidence Level

Moderate human trials (Phase 1-2)

FDA Status

FDA approved for this use

Safety Overview

Aprepitant (the primary NK1 antagonist) has been FDA-approved since 2003 with extensive safety data in over 50,000 cancer patients receiving highly emetogenic chemotherapy. Most common adverse events are mild to moderate—headache (15-20%), fatigue, and constipation—which are often difficult to attribute solely to aprepitant versus underlying malignancy or chemotherapy effects. Serious but rare adverse events include Stevens-Johnson syndrome (extremely uncommon) and QT prolongation (in susceptible individuals), requiring baseline ECG evaluation in high-risk patients.

Contraindications

  • xSevere hypersensitivity to aprepitant or any component
  • xConcurrent use with certain other medications that affect the liver
  • xSevere cardiac conditions

TB-500

Evidence Level

Moderate human trials (Phase 1-2)

FDA Status

Research compound

Safety Overview

TB-500 has shown a good safety profile across preclinical studies and limited human research. It's a fragment of thymosin beta-4, a naturally occurring protein in your body involved in healing. Most side effects are mild and transient, primarily injection site reactions. However, large-scale clinical trials are still needed to fully establish its safety profile in humans.

Contraindications

  • xPregnancy or planning to become pregnant
  • xCurrently breastfeeding
  • xActive cancer or history of cancer
  • xKnown allergy to peptide components
  • xChildren and adolescents

Decision Guide

Which is
right for you?

Choose Substance P Antagonists if...

  • Managing severe nausea from cancer treatments
  • Chronic pain reduction
  • Improving quality of life during intensive medical therapy

Choose TB-500 if...

  • Accelerating injury recovery
  • Tendon and ligament healing
  • Reducing chronic inflammation
  • Post-surgical recovery support