Getting Started with Peptides: The Complete Beginner's Guide

What Are Peptides?

Peptides are short chains of amino acids — typically between 2 and 50 amino acids long. They’re essentially small proteins. Your body produces hundreds of different peptides naturally, and they serve as signaling molecules that tell your cells what to do. Hormones like insulin (51 amino acids) and oxytocin (9 amino acids) are peptides. Growth factors, neurotransmitters, and antimicrobial defenders in your immune system are peptides.

The peptides sold in the research market are synthetic versions of naturally occurring peptides, modified analogs designed for improved stability or potency, or entirely novel sequences designed to target specific biological pathways.

The Regulatory Landscape: What You Need to Know

The “Research Chemical” Framework

Most peptides sold online are marketed as “research chemicals” or “for laboratory use only — not for human consumption.” This legal framing exists because:

1. FDA approval is expensive: Clinical trials cost $1-2 billion and take 10-15 years. Most peptides will never generate enough revenue to justify this investment.
2. Patent limitations: Many peptides are natural sequences that can’t be patented, removing the financial incentive for pharmaceutical development.
3. Legal grey area: Selling peptides as research chemicals is technically legal; selling them as drugs for human use is not.

What This Means for You

• No peptide sold as a “research chemical” has been through human clinical safety trials for that specific formulation
• “Research grade” purity (95-99%) is not the same as pharmaceutical grade
• You are the de facto clinical trial when you use a research peptide
• Some peptides (like semaglutide, tirzepatide, bremelanotide/PT-141) DO have FDA-approved pharmaceutical versions — the approved versions are always preferable when accessible

FDA Enforcement Trends

The FDA has dramatically increased enforcement against peptide vendors since 2024:

• Warning letters to vendors selling semaglutide and tirzepatide
• BPC-157 added to the “do not compound” list (November 2024)
• ITC exclusion orders against tirzepatide importers
• The compounding exception for semaglutide ended in early 2025

Categories of Popular Peptides

Recovery & Healing

• BPC-157: Gastric juice-derived peptide researched for tendon, gut, and tissue healing
• TB-500: Thymosin beta-4 — researched for wound healing, cardiac repair, neuroprotection
• GHK-Cu: Copper peptide — skin regeneration, wound healing, anti-aging

Metabolic / Weight Management

• Semaglutide: GLP-1 agonist (FDA-approved as Ozempic/Wegovy)
• Tirzepatide: Dual GIP/GLP-1 agonist (FDA-approved as Mounjaro/Zepbound)
• Retatrutide: Triple agonist (GIP/GLP-1/Glucagon) — experimental, not approved

Growth Hormone Secretagogues

• Ipamorelin: Selective GH secretagogue
• CJC-1295: GHRH analog (often paired with ipamorelin)
• GHRP-6 / GHRP-2: Older, less selective GH secretagogues

Anti-Aging

• Epithalon: Telomerase activator derived from pineal gland research
• GHK-Cu: Gene expression modulation and skin regeneration

Anti-Inflammatory

• KPV: Alpha-MSH fragment, NF-kB inhibitor, gut health focus
• BPC-157: Also categorized here for anti-inflammatory properties

Sexual Health

• PT-141 (Bremelanotide): Melanocortin agonist (FDA-approved as Vyleesi for HSDD)
• Melanotan II: Tanning + sexual arousal (NOT FDA-approved, significant side effects)

How to Evaluate a Peptide Vendor

This is where PeptideExaminer earns its name. Here’s what to look for:

Non-Negotiable Requirements

1. Published Certificates of Analysis (COAs): Real vendors publish third-party testing results showing identity, purity, and potency for each batch
2. Third-party testing: Testing must be performed by an independent laboratory, not the vendor’s own internal lab
3. Batch-specific results: COAs should correspond to specific lot numbers, not be generic documents
4. Verifiable business presence: Physical address, named ownership, registered business entity

Strong Positives

• Finnrick Analytics inclusion: Independent testing database that verifies vendor claims
• HPLC and mass spectrometry data: The gold standard analytical methods for peptide verification
• Endotoxin testing: Critical for injectable products — bacterial endotoxins can cause severe reactions
• GMP manufacturing claims with documentation: Good Manufacturing Practice compliance
• Credit card acceptance: Payment processor vetting provides some legitimacy signal
• BBB listing: Business Bureau presence indicates willingness to face public accountability

Red Flags

• No COAs or testing evidence: Walk away
• Cryptocurrency-only payment: Removes consumer fraud protections
• FDA warning letters or ITC enforcement actions: Check our vendor profiles
• Aggressive health claims: “Cures,” “treats,” or specific disease claims violate federal law
• Affiliate/influencer marketing with discount codes: Indicates marketing-driven rather than quality-driven business model
• Domain switching or multiple websites: Can indicate enforcement evasion
• Too-good-to-be-true pricing: Peptide synthesis has real costs; extreme discounts suggest quality compromise

How to Read a COA

We have a detailed guide on reading COAs, but the essentials:

• Identity test: Confirms the peptide is what it claims to be (usually mass spectrometry)
• Purity (HPLC): Should be 98%+ for research grade; >99% is excellent
• Appearance: Visual inspection (should be white/off-white powder)
• Net peptide content: The actual active peptide mass (vs. salt and moisture content)
• Endotoxin levels: For injectables, should be <5 EU/mg

Understanding Peptide Forms

Lyophilized Powder (Most Common)

• Freeze-dried powder in sealed vials
• Requires reconstitution with bacteriostatic water before use
• Most stable form for storage and shipping
• This is what most grey-market vendors sell

Injectable Solutions (Pre-Mixed)

• Ready-to-use solutions
• Less common from grey-market vendors
• Shorter shelf life than lyophilized powder
• Pharmaceutical products (Ozempic, Mounjaro) come in pre-filled injection pens

Oral Capsules

• Contain peptide powder in gelatin or vegetarian capsules
• Bioavailability varies enormously by peptide
• Small peptides (KPV, epithalon, GHK-Cu) have better theoretical oral absorption
• Large peptides (TB-500, semaglutide) have essentially zero oral bioavailability without specialized delivery technology
• Some products use enteric coating, liposomal encapsulation, or SNAC technology to enhance absorption

Topical Formulations

• Creams, serums, and patches
• Primarily used for GHK-Cu (copper peptide skincare)
• Some BPC-157 and TB-500 topical products exist but evidence for skin-penetration delivery is limited

Nasal Sprays

• Used for some peptides (PT-141, some nootropic peptides)
• Nasal mucosa provides a route to bypass GI degradation
• Dosing consistency can be challenging

Storage and Handling Basics

• Lyophilized peptides: Store at -20C for long-term storage; room temperature for short-term (weeks)
• Reconstituted peptides: Store at 2-8C (refrigerator); use within 2-4 weeks
• Never freeze reconstituted peptides: Ice crystal formation damages peptide structure
• Protect from light: Many peptides are light-sensitive
• Bacteriostatic water: Use only bacteriostatic water (not sterile water or saline) for reconstitution of multi-use vials — the benzyl alcohol preservative prevents bacterial growth
• Sterile technique: Alcohol-swab vial tops before each use; use new needles for each injection

Cost Expectations

Peptide costs vary enormously based on:

• Peptide complexity: Longer sequences cost more to synthesize
• Purity level: >99% costs more than 95%
• Testing: Vendors who actually test their products charge more
• Vendor margin: The markup between synthesis cost and retail price

Rough Price Ranges (Grey Market, Per Vial)

• BPC-157 (5mg): $25-60
• TB-500 (5mg): $30-70
• Ipamorelin (5mg): $25-50
• GHK-Cu (50mg): $30-60
• Semaglutide (5mg): $50-150
• PT-141 (10mg): $30-60

If a price seems dramatically below these ranges, question purity and authenticity. Legitimate peptide synthesis has real costs.

Before You Start: Safety Checklist

1. Research the specific peptide thoroughly (start with our scientific profiles)
2. Understand that no grey-market peptide has FDA-approved human safety data
3. Consult with a healthcare provider, ideally one knowledgeable about peptide therapy
4. Verify vendor quality using our vendor report cards
5. Check the COA for your specific batch
6. Start with the lowest effective dose cited in research literature
7. Have a plan for monitoring effects and side effects
8. Know when to stop and seek medical attention
9. Never combine peptides without understanding potential interactions
10. Be honest with yourself about why you’re using peptides and whether approved alternatives exist

PeptideExaminer’s Role

We don’t sell peptides. We don’t have affiliate relationships. We exist to provide you with the independent information you need to make informed decisions in a market that is flooded with vendor marketing, influencer shilling, and incomplete science. Read our vendor report cards, understand the science behind each peptide, and approach this space with appropriate caution.

---

PeptideExaminer — We don’t sell peptides. We tell you the truth about them.