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Grey-Market Encyclopedia · Buyer's guide

The grey-market buyer's guide: start here

Twelve steps in the order a first-time buyer meets them, from whether an approved option exists to what to keep and whom to tell if something goes wrong. Each step says what to decide and why, and links the page that covers it in full. It does not tell anyone to buy, and it names no seller.

Last updated October 28, 2026 · Reviewed by Grey Peptides Editorial Board · ✓ Every claim sourced · No products sold, no seller named

📋 Key takeaways

Start by asking whether an approved or prescribed product exists for the goal. Compounded drugs are not FDA-approved either, but they are made by a licensed pharmacy on a prescription;2 a grey-market vial has neither.1

Nothing on the label or the certificate guarantees what is in a vial: when researchers bought semaglutide vials from online sellers, semaglutide made up only 7.7% to 14.37% of the powder.10 Read a certificate with the checklist, and look for independent results.

Payment decides your recourse. The FTC says crypto payments "typically are not reversible",5 while a card charge for goods not delivered as agreed can be disputed in writing.7

Use water from a labelled, sealed source, a new sterile needle and syringe every time,12 and take a dose only from an entry's dosing box, which names its source. FDA has documented people injecting five to 20 times the intended dose through unit and volume mix-ups.14

Keep the vial, the lot number and the order records. Report a bad reaction or a bad product to FDA's MedWatch,16 and fraud to the FBI's complaint centre, which asks for the records.17

On this page

  1. How to use this guide
  2. Step 1: Check whether an approved or prescribed option exists
  3. Step 2: Know the legal position
  4. Step 3: Learn how sellers are found, the scams, and how you will pay
  5. Step 4: Judge the seller's paperwork, and look for independent tests
  6. Step 5: Compare offers by price per milligram, and size the order
  7. Step 6: Understand domestic versus international shipping
  8. Step 7: Get the supplies: labelled water and new syringes
  9. Step 8: Reconstitute with the calculator, not mental arithmetic
  10. Step 9: Store it, and know when to throw it away
  11. Step 10: Take dose information only from the entry's dosing box
  12. Step 11: Know which reactions are expected and when to get care
  13. Step 12: Keep records, and report problems
  14. Printable checklist
  15. Frequently asked questions
  16. Related on Grey Peptides
  17. Sources

How to use this guide

The steps follow the order in which a first-time buyer meets each decision: whether to buy at all, then whom to trust, then what to buy, then how to handle it, then what to do when something goes wrong. Each step is short on purpose. It says what to decide and why, and links the page on this site that covers the topic in full, with its own sources. The checklist at the end sums up all twelve steps on one page you can print.

The guide is written for harm reduction. It does not tell anyone to buy, and it does not tell anyone not to; the grey-market hub sets out why people buy and what they give up. It names no seller, gives no dose amount, and says nothing about getting a parcel past customs or any other check.

Step 1: Check whether an approved or prescribed option exists

Decide: is there a product a clinician can prescribe for the reason you are buying?

Why it comes first: an approved drug is a specific product whose maker answers to a regulator for what is in it. A grey-market vial is not: FDA has warned companies that sold drugs "falsely labeled 'for research purposes' or 'not for human consumption'" directly to consumers with dosing instructions.1 In between sit compounded drugs, which "are not FDA-approved" but are made by a state-licensed pharmacy or physician on a patient-specific prescription, or by an FDA-registered outsourcing facility.2 For many goals people buy peptides for, such as weight loss, growth hormone or low sexual desire, an approved medicine already exists, and for two of them the approved product is the same molecule sold online.

Use: the Approved-Alternative Finder. Pick the peptide you were going to buy, or the goal, and it lists the FDA-approved options, who each label says it is for, any boxed warning, and a link to the label. It also says plainly where nothing is approved. Take what it shows to a clinician; an approval covers specific people, and only a clinician can say whether it covers you.

Decide: whether you accept the legal position where you live, before money changes hands.

Why: in the US, a peptide sold for people to take without FDA approval is an unapproved drug, whatever its label says.1 For buyers, FDA says that "in most circumstances, it is illegal for individuals to import drugs or devices into the U.S. for personal use", and describes its personal-importation policy as discretion in narrow cases.3 As of March 2026, a refused drug worth $2,500 or less that arrives by international mail or express courier can be destroyed without an option to send it back, after FDA sends a notice.4 Athletes have a second rulebook: anti-doping rules ban some of these compounds at all times.

Read: the legal risks page for FDA status, research-use labels, personal importation, state rules, anti-doping and how Canada, Australia and the UK differ, and what 'research use only' means. If a parcel is held, our customs seizures article explains the notices. This is a description of the law, not legal advice.

Step 3: Learn how sellers are found, the scams, and how you will pay

Decide: how you will judge a seller you have never dealt with, and how you will pay.

Why: buyers mostly find sellers through forums, chat channels, influencers and search, and each route has its own scams: impersonated sellers, fake reviews, fake shipping messages, and demands to pay again for a "seized" parcel. Some FTC advice applies directly. Before paying, search the seller's name with words like "review", "complaint" or "scam", and treat steeply discounted name-brand goods as possible fakes.9 "Anyone who insists that you pay by gift card is always a scammer."6 Crypto payments "typically are not reversible" and "do not come with legal protections".5 A credit card is different: under the Fair Credit Billing Act a card holder can dispute a charge for goods not delivered as agreed, in writing to the card issuer within 60 days after the first bill showing the charge.7 Many grey-market sellers take only crypto, so a buyer often chooses between a seller and a form of recourse (our reasoning).

Read: how buyers find sellers, and the scams, which describes each channel generically and the scams common to it, and financial risks for payment, chargebacks, exit scams and orders that never ship.

Step 4: Judge the seller's paperwork, and look for independent tests

Decide: what evidence you need that the vial holds what its label says.

Why: the certificate of analysis a seller posts is usually the only quality evidence a buyer sees, and it describes a sample the laboratory received, not necessarily your vial. Labels can be far off. In a 2024 study, researchers bought semaglutide vials from online sellers without a prescription; semaglutide made up only 7.7% to 14.37% of the powder, and the prefilled pens they ordered never arrived.10 Purity is not the only question: a certificate can show a clean sample and still say nothing about endotoxin or sterility.

Use: the 60-second fake COA checklist (lot and date, purity method, chromatogram, mass, endotoxin, laboratory, and whose sample it was), the COA Decoder that applies the same checks, how to check a seller's claims, and published test results, where every row names the laboratory, the method and where the result was published, failures included.

Step 5: Compare offers by price per milligram, and size the order

Decide: one vial or a kit, and which offer is really cheaper.

Why: listings show a price per vial, which hides the comparison that matters: the cost per milligram of the same compound, which is the price divided by the number of vials times the milligrams in each. A single vial can cost many times a kit's price per vial, and nothing on the listing says so. A kit has its own cost: ten vials from one batch is one risk taken ten times, and it is ten vials to store. If you count the cost of testing, include it in the price (our reasoning).

Use: kits versus single vials for the arithmetic, worked, and the price-per-mg calculator, which takes two offers and shows each per vial and per milligram. You do not pick a peptide, and it carries no prices.

Step 6: Understand domestic versus international shipping

Decide: what a seller's shipping claim does and does not tell you.

Why: some overseas sellers import stock in bulk and ship orders from inside the US. That changes the last leg: delivery is usually faster, and the buyer's own parcel is not an import. It does not change what the product is, who made it, or its legal status: FDA's position on unapproved drugs applies inside the US as well as at the border.1 A parcel that does come from abroad is an import, and a refused drug parcel can be destroyed.4 A seller who says "US stock" and ships from abroad has made one claim that was not accurate, which is worth weighing against its other claims (our reasoning).

Read: US warehouses and domestic stock, which describes how the model works and how a buyer can check the shipping claim from the carrier and tracking, and the 2025 China crackdown on what happens to buyers when a supplier disappears. Neither page, and not this one, gives advice on avoiding customs.

Step 7: Get the supplies: labelled water and new syringes

Decide: where the water and the injecting equipment will come from.

Why: most research vials hold a dry powder that has to be dissolved before use, and what it is dissolved in goes into the body too. Bacteriostatic water for injection is, in its approved label's words, "a sterile, nonpyrogenic preparation of water for injection" with benzyl alcohol added as a preservative, in a multiple-dose container "from which repeated withdrawals may be made"; the label also says it is not for use in newborns.11 Of the bacteriostatic waters listed on DailyMed on October 28, 2026, one was FDA-approved; our guide names it and explains what an NDC does and does not prove. A sealed, labelled vial has a maker, a lot and an expiry date behind it; an unlabelled one has none (our reasoning). For injecting, CDC's rule for clinicians is to "use a new sterile syringe and needle" each time and never to reuse one on another person.12 FDA says used sharps "should be immediately placed in a sharps disposal container", and that if an FDA-cleared one is not available, "a heavy-duty plastic household container, such as a laundry detergent container" can be used instead.13

Read: the bacteriostatic water guide (approved products from their labels, how long a vial lasts, and what not to use instead) and its grey-market summary on contamination and reactions, which covers why the water and sterility matter. For the syringes themselves, our syringes section covers whether you can buy them without a prescription in your state, sizes, needles and units versus mL, injecting under the skin and reuse, sterility and sharps disposal.

Step 8: Reconstitute with the calculator, not mental arithmetic

Decide: how much water to add, and how much to draw for a dose you have taken from a sourced box (step 10).

Why: the amount of water sets the concentration, and the concentration sets how much liquid holds a dose. Mistakes here are not hypothetical: FDA has reported patients who gave themselves five to 20 times the intended dose of compounded semaglutide, with confusion between millilitres, milligrams and "units", and syringes much larger than the prescribed volume.14 Approved peptide labels set the visual check: the tesamorelin label says not to use the solution if solid particles appear or it is cloudy or coloured.15 Our reconstitution guide covers adding the liquid gently and not shaking, from the labels it cites. CDC adds: "Do not leave a needle inserted into a medication vial septum for multiple uses."12

Use: how to reconstitute peptides for the steps and their sources, and the reconstitution calculator, which takes vial size, water and dose and shows the draw in syringe units; it never asks you to pick a peptide. The peptide mixing chart lays the same arithmetic out as a table.

Step 9: Store it, and know when to throw it away

Decide: where the vials will live, and the date a mixed vial is discarded.

Why: research peptides come with no tested storage conditions, so the practice borrows from approved products and public-health guidance. CDC's storage guidance for vaccines warns against the refrigerator's door shelves, its drawers and the space directly under cooling vents.18 The bacteriostatic water label says a drug dissolved in it should be used promptly and not stored unless the drug's maker directs otherwise.11 The 28 days often quoted is a sterility limit for an opened multiple-dose vial from a manufacturer: CDC, citing the US Pharmacopeia, says such a vial "should be dated and discarded within 28 days".12 It is an outer limit for sterility, not a measure of how long a peptide stays intact (our reasoning from the source's scope).

Read: how to store peptides for powder, mixed vials, travel and when to throw a vial away. Write the date on a vial the first time you puncture it; the reconstitution calculator has a 28-day tracker for that.

Step 10: Take dose information only from the entry's dosing box

Decide: where your dose comes from, before you mix anything.

Why: a dose a seller prints on a listing is the seller's figure, not evidence. Every encyclopedia entry on this site opens with a Recommended dosing box, and each row in it names its source: a manufacturer's label, a published human trial, a published report marked unverified, or no established human dose at all. Where an FDA label exists, the box gives the label's dosing and links it; for many peptides sold online there is none, and the box says so rather than filling the gap. This guide gives no dose amounts: see the box on the entry for the compound, for example BPC-157's dosing box, and that entry's What a Buyer Needs section. A trial's dose was tested in a trial's conditions, on a product whose content was known; a grey-market vial's real content can differ from its label,10 which changes the dose you actually get (our reasoning). See a doctor before starting, stopping or changing any medicine.

Step 11: Know which reactions are expected and when to get care

Decide: in advance, what you will watch for and what will make you stop and get care.

Why: some local reaction is common even with approved peptides. The tesamorelin label reports injection-site reactions such as redness, itching, pain and bruising in 25% of treated patients against 14% on placebo in its trials, and advises rotating sites.15 Other signs are not routine: spreading redness, warmth, increasing pain, pus or fever can mean infection, and slow infections from contaminated products can appear weeks later. Products made for research are not made or tested as sterile medicines for people, which adds a risk that technique cannot fully remove.

Read: peptide injection-site reactions, which has a table of what you see, what it usually means and what to do, and contamination and skin reactions for rashes, allergic reactions and a when-to-get-care list. If you feel unwell after taking a product, contact a clinician or Poison Help (1-800-222-1222 in the US), and say what you injected. Both linked pages list the signs of a severe allergic reaction that need emergency care at once.

Step 12: Keep records, and report problems

Decide: what you will keep, starting from the order.

Why: records are what a clinician, a regulator or an investigator works from. Keep the vial and its label, the lot number, the certificate as posted, the order confirmation, the payment record and the messages with the seller (our list, from what the sources below ask for). The FBI's Internet Crime Complaint Center asks people to keep financial records such as card, wire, cryptocurrency and prepaid-card receipts, shipping records, emails with full headers, web page copies and chat transcripts, because an investigating agency may ask for them.17 A health problem or a product that looks wrong can be reported to FDA's MedWatch program, which takes reports from patients and consumers as well as clinicians, online, with Form 3500B or by phone.16 A fraud can be reported to the FBI's complaint centre.17 After a loss, be wary of anyone who offers to recover the money: the FTC warns that refund and recovery offers are a common follow-on scam, that a legitimate helper will not charge upfront, and that none can guarantee your money back.8

Read: contamination and reactions for what a MedWatch report should include, and sources and scams and financial risks for reporting fraud.

Printable checklist

The twelve steps on one page. Print it with your browser's print command; each line links the step above that explains it.

First-time buyer's checklist

☐ 1. Approved option: I checked the Approved-Alternative Finder and asked a clinician whether a prescribed product fits.

☐ 2. Law: I know the product is an unapproved drug in the US, and what personal importation and destruction of refused parcels mean.34

☐ 3. Seller and payment: I searched the seller's name with "review", "complaint" and "scam";9 I will not pay by gift card;6 I know a crypto payment usually cannot be reversed.5

☐ 4. Testing: I ran the certificate through the seven COA checks and looked for independent results on the compound.

☐ 5. Price: I compared offers per milligram, with shipping and testing included, and sized the order to what I can store and lose.

☐ 6. Shipping: I know what "US stock" changes (delivery) and what it does not (legal status, quality).

☐ 7. Supplies: sealed, labelled bacteriostatic water;11 new sterile needles and syringes for every injection;12 a sharps container.13 See Syringes for first-timers.

☐ 8. Mixing: I used the reconstitution calculator, checked the solution is clear, and never leave a needle in the stopper.12

☐ 9. Storage: in the refrigerator's main body, not the door;18 date written on first puncture; a mixed vial used promptly, and never past 28 days, a sterility limit.1112

☐ 10. Dose: taken only from the entry's dosing box and its named source, after talking to a doctor.

☐ 11. Reactions: I know the signs of infection and allergy, and the Poison Help number, 1-800-222-1222 (US).

☐ 12. Records: vial, lot, certificate, order, payment and messages kept; MedWatch for health or product problems,16 IC3 for fraud.17

Frequently asked questions

Where should a first-time buyer start?

With whether an approved or prescribed product exists for the goal. Compounded drugs are not FDA-approved but are made by licensed pharmacies on a prescription; grey-market vials are sold without either.12

Does this guide recommend a seller or a dose?

No. It names no seller and gives no dose amounts. Doses, where a credible source gives one, are in each encyclopedia entry's dosing box with that source named.

Is it legal to import peptides for personal use in the US?

FDA says that in most circumstances it is illegal for individuals to import drugs for personal use, and that its personal-importation policy is discretion in narrow cases.3

Can I get my money back if an order never arrives?

A card charge for goods not delivered as agreed can be disputed in writing within 60 days of the first bill showing it; the FTC says crypto payments typically are not reversible.57

How long can I keep a mixed vial?

The water's label says to use a dissolved drug promptly. The 28 days often quoted is CDC's sterility limit for an opened multiple-dose vial from a manufacturer, an outer limit rather than a keeping time.1112

Where do I report a bad reaction or a bad product?

To FDA's MedWatch program, which takes reports from patients and consumers, online, with Form 3500B or by phone; fraud goes to the FBI's Internet Crime Complaint Center.1617

Grey market hub Physical risks Financial risks Legal risks How buyers find sellers, and the scams The 2025 China crackdown Contamination and skin reactions US warehouses and domestic stock What 'research use only' means Chinese peptides explained Peptide raves and group buys Peptides on Amazon, Temu and TikTok Shop How to evaluate a peptide vendor Purity is not safety Grey-market glossary

Sources

Regulators' pages and drug labels are cited with the dates they show; one peer-reviewed product test was read at PubMed. All read October 28, 2026. Each step links the page on this site that owns the topic, where its other facts are sourced. Where a sentence is our own inference it says '(our reasoning)'.

  1. U.S. Food and Drug Administration. FDA's concerns with unapproved GLP-1 drugs used for weight loss. Content current as of October 1, 2026; read October 28, 2026. Source
  2. U.S. Food and Drug Administration. Compounding Laws and Policies (sections 503A and 503B of the FD&C Act). Content current as of December 17, 2024; read October 28, 2026. Source
  3. U.S. Food and Drug Administration. Personal Importation (Import Basics). Content current as of August 18, 2025; read October 28, 2026. Source
  4. U.S. Food and Drug Administration. Administrative Destruction Authority (Import Basics). Content current as of March 16, 2026; read October 28, 2026. Source
  5. Federal Trade Commission. What To Know About Cryptocurrency and Scams. Consumer advice, last modified February 10, 2025; read October 28, 2026. Source
  6. Federal Trade Commission. Did someone tell you to pay with gift cards? It's a scam. Consumer alert, September 2020; read October 28, 2026. Source
  7. Federal Trade Commission. Using Credit Cards and Disputing Charges (the Fair Credit Billing Act). Consumer advice, last modified April 2, 2024; read October 28, 2026. Source
  8. Federal Trade Commission. Refund and Recovery Scams. Consumer advice, December 14, 2023, last modified August 13, 2026; read October 28, 2026. Source
  9. Federal Trade Commission. Shopping online? Know your retailer and your rights. Consumer blog, June 30, 2021; read October 28, 2026. Source
  10. Ashraf AR, et al. Multifactor Quality and Safety Analysis of Semaglutide Products Sold by Online Sellers Without a Prescription: Market Surveillance, Content Analysis, and Product Purchase Evaluation Study. J Med Internet Res. 2024;26:e65440. PMID 39509151; abstract read October 28, 2026. Source
  11. Hospira, Inc. Bacteriostatic Water for Injection, USP (NDA 018802), prescribing information: sterile, nonpyrogenic water for injection with benzyl alcohol as a bacteriostatic preservative; multiple-dose container; not for use in neonates; use dissolved drugs promptly and do not store them unless the drug's maker directs otherwise. DailyMed set 87d6e9dc, version 20, effective May 22, 2026; read October 28, 2026. Source
  12. Centers for Disease Control and Prevention. Preventing Unsafe Injection Practices (Injection Safety: clinical safety), last reviewed March 26, 2024: a new sterile syringe and needle for each patient; an opened multi-dose vial from a manufacturer dated and discarded within 28 days, a sterility limit (citing USP General Chapter 797); do not leave a needle in a vial septum. Read October 28, 2026. Source
  13. U.S. Food and Drug Administration. Safely Using Sharps (Needles and Syringes) at Home, at Work and on Travel. Content current as of November 19, 2021; read October 28, 2026. Source
  14. U.S. Food and Drug Administration. FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products. July 26, 2024 (content current as of July 26, 2024); read October 28, 2026. Source
  15. Theratechnologies. EGRIFTA WR (tesamorelin) US prescribing information, sections 2 and 5.6 (injection site reactions; do not use if solid particles appear or the solution is cloudy or colored). DailyMed set 839334d3, version 2, effective July 29, 2026; read October 28, 2026. Source
  16. U.S. Food and Drug Administration. Reporting Serious Problems to FDA (MedWatch). Content current as of September 26, 2025; read October 28, 2026. Source
  17. Federal Bureau of Investigation, Internet Crime Complaint Center. Frequently Asked Questions (retaining evidence; what IC3 does with complaints). No date shown; read October 28, 2026. Source
  18. Centers for Disease Control and Prevention. Vaccine Storage and Handling Toolkit, July 2026 (updated July 14, 2026), Section Three: avoid storing vaccines directly under cooling vents, in deli, fruit or vegetable drawers, or on refrigerator door shelves. Read October 28, 2026. Source

This guide describes the decisions and checks a first-time buyer faces; it is not legal or medical advice and it is not a recommendation to buy. Grey Peptides sells nothing, links to no seller and rates none. If you have taken a product and feel unwell, contact a clinician or Poison Help (1-800-222-1222 in the US).