Peptide Safety Guide

General safety principles#

Start with the lowest effective dose and titrate up slowly. Never begin multiple new peptides at the same time — if something goes wrong, you won't know what caused it. Get baseline bloodwork before starting any protocol. Research your specific peptide thoroughly before use, as mechanisms and risk profiles vary significantly between classes.

Common side effects by class#

GH secretagogues (CJC-1295, Ipamorelin, GHRP-6): water retention, increased hunger, tingling hands, temporary insulin resistance at high doses. GLP-1 agonists (Semaglutide, Tirzepatide): nausea, constipation, reduced appetite — usually dose-dependent and transient. Healing peptides (BPC-157, TB-500): generally very well tolerated; mild nausea reported rarely. Tanning peptides (Melanotan II): nausea, flushing, spontaneous erections, moles darkening — use extreme caution.

Injection site reactions#

Mild redness, itching, or a small welt at the injection site is common and usually resolves within an hour. Persistent swelling, warmth, or a lump that lasts more than 24 hours may indicate infection or improper injection technique. Rotate injection sites to avoid tissue buildup. Never reuse needles — each injection should use a fresh syringe.

When to stop#

Discontinue use and consult a physician if you experience: severe or worsening injection site reactions, systemic symptoms (fever, chills, rash spreading beyond the injection site), unusual changes in blood pressure or heart rate, vision changes, or any symptom that feels disproportionate. Most peptide side effects are dose-dependent — reducing the dose is often the first appropriate step.

Run bloodwork before and during any protocol. The Reading Your Bloodwork guide explains which markers to track.

What to avoid#

Do not share vials or syringes. Do not use peptides from suppliers who cannot provide third-party certificates of analysis. Avoid stacking multiple peptides from the same class simultaneously until you understand how each affects you individually. Do not use GH secretagogues if you have a personal or family history of cancer — growth hormone stimulation is contraindicated in active malignancy.