This guide explains how injectable peptides are stored, measured, mixed, injected and thrown away, and how to recognise when something has gone wrong. It exists to reduce harm. It is not a how-to for getting started, and nothing here says that any substance is a good idea for you.
Two things are true of almost everything on this site, and they shape the whole guide:
- Approved medicines come with tested instructions. The storage times, injection sites and missed-dose rules on a product's label were worked out for that exact product. Where this guide and a label disagree, the label wins.
- Unapproved products come with no tested instructions. There is no validated shelf life, no confirmed dose and no guarantee that the vial holds what its label says. Careful handling lowers some risks (infection, measuring mistakes). It does nothing about the others (wrong contents, impurities, unknown long-term effects).
The six-step path
- Read the emergency page first. Know the signs that mean "call an ambulance" before you ever need them: /guide/emergency/.
- Look up the substance. Every peptide page (
/peptides/<slug>/) shows an evidence grade, its legal status, reported dose ranges with their context, and safety notes. Use the goal finder (/goals/), the comparison tool (/compare/) and the stack explorer (/stacks/) to see how thin or strong the evidence is. Read "Method & disclaimer" (/method/) to understand what the grades and user statistics can and cannot tell you. - Check whether you are in a group that should not do this at all (the list is below), and talk to a clinician.
- Learn storage and the discard rules. /guide/storage/ and /guide/warning-signs/.
- Learn the arithmetic and the technique. /guide/mixing-math/, /guide/reconstitution/ and /guide/injection-basics/. Measuring errors are a documented cause of serious home dosing mistakes; regulators have received reports of overdoses, some needing hospital care, from people confusing milligrams, millilitres and syringe "units" [1].
- Know what comes after. /guide/side-effects/, /guide/troubleshooting/ and /guide/disposal/.
Who should not self-administer anything
If any line below describes you, the answer from this site is "do not inject anything on your own". Go through a clinician.
- You are under 18. These substances act on growth, appetite, hormones and development. None of the reference material on this site applies to children or teenagers.
- You are pregnant, trying to become pregnant, or breastfeeding. Almost none of these substances has been tested in pregnancy. Some approved peptides are contraindicated in pregnancy outright (tesamorelin is one example) [2], and the preserved diluent commonly used for mixing carries its own label caution in pregnancy and must never be used in newborns [3].
- You have a serious medical condition. In particular:
- active cancer or a history of cancer (drugs that raise growth hormone or IGF-1 carry a labelled warning about tumour growth and are contraindicated in active malignancy) [2];
- a personal or family history of medullary thyroid cancer or MEN 2 (a labelled contraindication for GLP-1-type drugs) [4][5];
- past pancreatitis or gallbladder disease [4][5];
- diabetes, especially if you use insulin or a sulfonylurea (risk of low blood sugar) [4][5];
- heart disease or blood pressure that is not controlled (a labelled contraindication for bremelanotide) [6];
- kidney or liver disease, a weakened immune system, a bleeding disorder, or an eating disorder.
- You take medicines that can interact. Examples that appear on approved labels: insulin and sulfonylureas (low blood sugar) [4][5]; medicines taken by mouth, including oral contraceptives, whose absorption can change when a drug slows stomach emptying [4]; blood-pressure medicines; blood thinners (bruising and bleeding at injection sites). A pharmacist can check your actual list in a few minutes.
- You have had a serious allergic reaction to any injected medicine or to an ingredient in the product.
- You have surgery or sedation planned. GLP-1-type drugs carry a labelled warning about food being inhaled into the lungs during anaesthesia [4][5]. Tell the surgical team what you take.
Talk to a clinician
A clinician who knows exactly what you are using can order the right blood tests, spot an interaction, and recognise a side effect early. A clinician who does not know cannot do any of that. Tell them the substance, the amount, how often, and for how long, even if you expect disapproval. If you are already using something and feel unwell, do not wait for an appointment to say so.
Sources
Checked 13 November 2026.
- U.S. Food and Drug Administration. "FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products" (26 July 2024). https://www.fda.gov/drugs/human-drug-compounding/fda-alerts-health-care-providers-compounders-and-patients-dosing-errors-associated-compounded
- Tesamorelin for injection (Egrifta WR), US prescribing information and instructions for use, DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=839334d3-8c1d-4c26-9036-2ab524a6ea75
- Bacteriostatic Water for Injection, USP (0.9% benzyl alcohol), US product labeling. (link not shown: non-primary host)
- Tirzepatide injection (Zepbound), US prescribing information, DailyMed. https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=487cd7e7-434c-4925-99fa-aa80b1cc776b&type=display
- Semaglutide (Wegovy), US prescribing information, DailyMed. https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=ee06186f-2aa3-4990-a760-757579d8f77b
- Bremelanotide injection (Vyleesi), US prescribing information, DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f1d0c1b5-2f39-4bad-a6a4-0066e3ad5dcf