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Peptide Database

Goals
Fat LossMuscle BuildingInjury HealingAnti-AgingCognitive EnhancementSleep OptimizationImmune SupportGut HealingSkin RejuvenationSexual Health
Peptides
Abarelix
Hormone Support
Acetyl Hexapeptide-3 (Argireline)
Cosmetic
Adipotide
Weight Management
Adrenomedullin
Healing & Recovery
Alexamorelin
Growth Hormone
Angiotensin (1-7)
Healing & Recovery
AOD-9604
Weight Management
Apelin-13
Healing & Recovery
ARA-290 (Cibinetide)
Healing & Recovery
Bestatin (Ubenimex)
Immune
BPC-157
Healing & Recovery
Buserelin
Hormone Support
Cagrilintide
Weight Management
Capromorelin
Growth Hormone
Cartalax
Anti-Aging
Cathelicidin (hCAP-18 / Synthetic Derivatives)
Immune
Cerebrolysin
Cognitive
Cerluten
Cognitive
Cetrorelix
Hormone Support
Chonluten
Immune
CJC-1295 (No DAC)
Growth Hormone
CJC-1295 with DAC
Growth Hormone
Copper Tripeptide-1 (GHK-Cu)
Cosmetic
Cortexin
Cognitive
Crystagen
Immune
Daptomycin
Immune
Defensin (HBD-2)
Immune
Defensin (HBD-3)
Immune
Degarelix
Hormone Support
Dihexa
Cognitive
DSIP (Delta Sleep-Inducing Peptide)
Sleep & Recovery
Dulaglutide
Weight Management
Enalapril
Healing & Recovery
Epithalon
Anti-Aging
Exenatide
Weight Management
Fertirelin
Hormone Support
Ganirelix
Hormone Support
GHK-Cu
Cosmetic
GHRH (1-29)
Growth Hormone
GHRP-2
Growth Hormone
GHRP-6 (Growth Hormone Releasing Peptide-6)
Growth Hormone
Gonadorelin (GnRH)
Hormone Support
Gramicidin
Immune
Hexarelin
Growth Hormone
Human Chorionic Gonadotropin (HCG)
Hormone Support
Human Growth Hormone (HGH)
Growth Hormone
IGF-1 LR3
Growth Hormone
Immunoxel (Dzherelo)
Immune
Imunofan
Immune
Intermedin (Adrenomedullin-2)
Healing & Recovery
Ipamorelin
Growth Hormone
Kisspeptin-10
Sexual Health
KPV (Alpha-MSH Fragment)
Healing & Recovery
Lactoferricin B
Immune
Larazotide
Healing & Recovery
Lentinan
Immune
Leuphasyl
Cosmetic
Leuphasyl
Cosmetic
Leuprolide
Hormone Support
Liraglutide
Weight Management
Livagen
Anti-Aging
Lixisenatide
Weight Management
LL-37
Immune
Macimorelin
Growth Hormone
Magainin-2
Immune
Mazdutide
Weight Management
Melanotan-2
Cosmetic
MK-677 (Ibutamoren)
Growth Hormone
MOTS-c
Metabolic
Myristoyl Pentapeptide-17
Cosmetic
N-Acetyl Selank
Cognitive
N-Acetyl Semax Amidate
Cognitive
NAD+
Mitochondrial
Nafarelin
Hormone Support
Natriuretic Peptide (ANP)
Healing & Recovery
Nesiritide (BNP)
Healing & Recovery
Nisin
Immune
Noopept (Omberacetam)
Cognitive
Orforglipron
Weight Management
Ovagen
Anti-Aging
Oxytocin Acetate
Hormone Support
P21 (P021)
Cognitive
PACAP-38
Healing & Recovery
Palmitoyl Oligopeptide
Cosmetic
Palmitoyl Pentapeptide-4 (Matrixyl)
Cosmetic
Palmitoyl Tetrapeptide-7
Cosmetic
Palmitoyl Tripeptide-1
Cosmetic
Pancragen
Metabolic
PEG-MGF
Healing & Recovery
Pemvidutide
Weight Management
Pentadecapeptide (BPC Analog)
Healing & Recovery
Pidotimod
Immune
Pinealon
Cognitive
PNC-27
Immune
Polymyxin B
Immune
Pralmorelin (GHRP-2)
Growth Hormone
Pramlintide
Weight Management
Prostamax
Hormone Support
PT-141 (Bremelanotide)
Sexual Health
Relaxin-2 (Serelaxin)
Healing & Recovery
Retatrutide
Weight Management
Selank
Cognitive
Semaglutide
Weight Management
Semax
Cognitive
Sermorelin
Growth Hormone
Setmelanotide
Weight Management
SLU-PP-332
Metabolic
SM-130686
Growth Hormone
Snap-8
Cosmetic
SS-31 (Elamipretide)
Mitochondrial
Substance P Antagonists
Healing & Recovery
Survodutide
Weight Management
SYN-AKE
Cosmetic
Tabimorelin
Growth Hormone
TB-500
Healing & Recovery
Tesamorelin
Growth Hormone
Testagen
Hormone Support
Thymalin
Immune
Thymopentin (TP-5)
Immune
Thymopoietin
Immune
Thymosin Alpha-1
Immune
Thymosin Beta-4
Healing & Recovery
Thymulin (FTS)
Immune
Thymulin Analog (PAT)
Healing & Recovery
Tirzepatide
Weight Management
Tripeptide-29
Cosmetic
Triptorelin
Hormone Support
Ularitide
Healing & Recovery
Urocortin
Healing & Recovery
Ventfort
Anti-Aging
Vesilute
Hormone Support
Vilon
Immune
VIP (Vasoactive Intestinal Peptide)
Healing & Recovery
Xenin-25
Metabolic
Ziconotide (Prialt)
Healing & Recovery
Total Peptides: 135
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Peptide Comparison

RetatrutidevsTirzepatide

The world's first triple-action weight loss peptide that simultaneously activates three hormone receptors—GIP, GLP-1, and glucagon—delivering unprecedented weight loss results of up to 24% body weight in clinical trials.

The dual-action powerhouse that targets both GIP and GLP-1 receptors, delivering the most dramatic weight loss results ever seen in a medication—averaging over 20% body weight reduction while also crushing blood sugar levels in people with diabetes.

Weight ManagementWeight Management

At a Glance

Quick
comparison

Dose Range

Retatrutide

1–12 mg

Tirzepatide

2.5–15 mg

Frequency

Retatrutide

Once weekly

Tirzepatide

Once weekly

Administration

Retatrutide

Subcutaneous injection

Tirzepatide

Subcutaneous injection

Cycle Length

Retatrutide

12+ weeks

Tirzepatide

Ongoing/indefinite

Onset Speed

Retatrutide

Moderate (1-2 weeks)

Tirzepatide

Moderate (1-2 weeks)

Evidence Level

Retatrutide

Moderate human trials (Phase 1-2)

Tirzepatide

Strong human trials (Phase 3 or FDA approved)

Efficacy

Benefit
ratings

Retatrutide
Tirzepatide

Weight Loss Power

Retatrutide98%
Tirzepatide0%

Metabolic Health

Retatrutide95%
Tirzepatide0%

Appetite Control

Retatrutide94%
Tirzepatide97%

Weight Loss

Retatrutide0%
Tirzepatide99%

Blood Sugar Control

Retatrutide0%
Tirzepatide96%

Technical Data

Compound
specifications

Retatrutide

Molecular Formula

C221H342N46O68

Molecular Weight

4731 g/mol

Half-Life

~6 days (allows once-weekly dosing)

Bioavailability

High via subcutaneous injection

CAS Number

2381089-83-2

Tirzepatide

Molecular Formula

C225H348N48O68

Molecular Weight

4813.45 g/mol

Half-Life

Approximately 5 days (120 hours)

Bioavailability

~80% (subcutaneous)

CAS Number

2023788-19-2

Protocols

Dosing
tiers

Retatrutide

starting

1-2 mg

Once weekly

4 weeks

Start low to let your body adjust. This minimizes the nausea and GI side effects that are most common when starting. Even at this low dose, you'll likely notice reduced appetite.

standard

4-8 mg

Once weekly

8-12 weeks

The sweet spot for most users. Clinical trials showed substantial weight loss at these doses with manageable side effects. Increase gradually (every 4 weeks) to reach this range.

advanced

12 mg

Once weekly

12+ weeks

Maximum studied dose delivering the most dramatic results—up to 24% weight loss. Only reach this after gradual titration and proving tolerance at lower doses. Side effects are more common but still manageable for most.

Tirzepatide

starting

2.5 mg

Once weekly

4 weeks

This introductory dose helps your body adjust to the medication and minimizes GI side effects. Don't expect much weight loss yet—this phase is all about building tolerance. Think of it as your body's training wheels period.

standard

5-10 mg

Once weekly

4+ weeks at each dose

After 4 weeks at 2.5mg, increase to 5mg. Stay here for at least 4 weeks, then move to 7.5mg, then 10mg. This gradual climb reduces side effects while ramping up the weight loss. Most people start seeing serious results at 5-10mg doses.

advanced

12.5-15 mg

Once weekly

Ongoing/maintenance

The 15mg dose delivers maximum weight loss—averaging over 20% of body weight in trials. Continue increasing by 2.5mg every 4 weeks until reaching 15mg or your optimal maintenance dose. This is where the jaw-dropping results happen.

Applications

Best
suited for

Retatrutide

Significant Obesity Management

If you need to lose a substantial amount of weight, retatrutide is showing unprecedented results. Phase 2 trials demonstrated average weight loss of 24% at the highest dose—that's nearly 60 pounds for someone weighing 250 lbs. No other medication has matched this.

Type 2 Diabetes with Obesity

Retatrutide tackles both problems at once. It dramatically improves blood sugar control (HbA1c reductions of up to 2%) while delivering major weight loss. The dual benefit makes it especially valuable for diabetics struggling with weight.

Metabolic Syndrome Warriors

If you're dealing with the cluster of issues that includes high blood sugar, excess belly fat, abnormal cholesterol, and high blood pressure, retatrutide's triple mechanism attacks multiple aspects of metabolic dysfunction simultaneously.

Fatty Liver Disease (MASLD)

Early research shows retatrutide may significantly reduce liver fat. For people with non-alcoholic fatty liver disease, this peptide offers hope through weight loss plus direct metabolic improvements that benefit liver health.

Tirzepatide

People Who Want Maximum Weight Loss Results

If you're serious about losing significant weight, tirzepatide delivers results that were previously only achievable through bariatric surgery. Clinical trials showed average weight loss exceeding 20% of body weight—that's 50+ pounds for someone starting at 250 pounds. No other medication comes close.

Those Who Haven't Succeeded with Semaglutide

Thanks to its dual GIP/GLP-1 mechanism, tirzepatide often works better for people who had limited results with GLP-1-only drugs like semaglutide. The added GIP activation provides extra metabolic benefits that can break through plateaus and deliver superior weight loss.

People with Type 2 Diabetes Needing Aggressive Control

Head-to-head trials proved tirzepatide beats semaglutide for blood sugar control. The average HbA1c reduction of over 2 percentage points means many people can dramatically reduce or eliminate other diabetes medications. It's a genuine game-changer for metabolic health.

Individuals Looking to Transform Their Relationship with Food

Tirzepatide doesn't just reduce hunger—it fundamentally changes how food appeals to you. Users describe feeling free from constant food thoughts, finding it easy to stop eating when satisfied, and losing interest in formerly irresistible treats. It's not willpower—it's biochemistry working for you.

Safety Profile

Side
effects

Retatrutide

Common

  • Nausea
  • Diarrhea
  • Constipation
  • Decreased appetite

Uncommon

  • Increased heart rate
  • Injection site reactions

Serious

  • Pancreatitis
  • Gallbladder problems

Tirzepatide

Common

  • Nausea
  • Diarrhea
  • Decreased Appetite
  • Vomiting

Uncommon

  • Gallbladder Problems
  • Hair Thinning (Telogen Effluvium)

Serious

  • Pancreatitis
  • Thyroid Tumors (Theoretical Risk)

Research Status

Safety
& evidence

Retatrutide

Evidence Level

Moderate human trials (Phase 1-2)

FDA Status

Research compound

Safety Overview

Retatrutide has shown a generally favorable safety profile in Phase 1 and Phase 2 clinical trials involving over 600 participants. Most side effects are gastrointestinal and tend to improve over time. The medication appears well-tolerated when doses are increased gradually. No major safety signals have emerged, but larger Phase 3 trials are still ongoing.

Contraindications

  • xPersonal or family history of medullary thyroid carcinoma (MTC)
  • xMultiple Endocrine Neoplasia syndrome type 2 (MEN 2)
  • xPregnancy or planning to become pregnant
  • xHistory of severe pancreatitis
  • xKnown allergy to GLP-1 receptor agonists

Tirzepatide

Evidence Level

Strong human trials (Phase 3 or FDA approved)

FDA Status

FDA approved for this use

Safety Overview

Tirzepatide has been extensively studied in the SURPASS (diabetes) and SURMOUNT (obesity) trial programs, involving thousands of participants over multiple years. The FDA approved it after thorough safety review. While GI side effects are common (especially during dose increases), they're typically mild to moderate and improve over time. Serious adverse events are rare. The SURPASS-CVOT trial is ongoing to evaluate long-term cardiovascular outcomes.

Contraindications

  • xPersonal or family history of medullary thyroid carcinoma (MTC)
  • xMultiple Endocrine Neoplasia syndrome type 2 (MEN2)
  • xHistory of serious allergic reaction to tirzepatide or any GLP-1/GIP medication
  • xCurrent or recent pancreatitis
  • xPregnancy or planning to become pregnant

Decision Guide

Which is
right for you?

Choose Retatrutide if...

  • Significant weight loss
  • Type 2 diabetes management
  • Metabolic health improvement
  • Body composition optimization

Choose Tirzepatide if...

  • Maximum weight loss results
  • Long-term obesity management
  • Type 2 diabetes control
  • Metabolic health improvement
Peptide ProRetatrutide vs Tirzepatide — Peptide Comparison | Peptide Initiative