The amount of peptide you inject depends entirely on which peptide you’re using, since dosages range from a fraction of a milligram to 10 milligrams or more per administration. There is no single universal dose. Each peptide has its own dosing range, titration schedule, and frequency, and getting the math right when you draw from a reconstituted vial is just as important as knowing the target dose itself.
Common Peptide Doses by Category
Peptides used for recovery, weight management, and growth hormone support each operate in very different dose ranges. Here’s what typical protocols look like for the most widely used compounds.
BPC-157: Injection dosing is typically based on body weight, ranging from 150 to 375 micrograms (mcg) twice daily. Most people land somewhere around 250 mcg per injection. It’s administered subcutaneously, often near the site of an injury, and cycles usually run four to six weeks.
TB-500 (Thymosin Beta-4): A standard loading protocol calls for 10 mg injected subcutaneously once per week for six weeks, then once monthly as a maintenance dose. Some protocols recommend timing the injection for the day after an intense workout.
CJC-1295 with Ipamorelin: These two growth hormone secretagogues are frequently combined in a single vial. A common dosing range is 0.05 to 0.1 mL of a combined solution injected at bedtime, five days per week. Ipamorelin has a half-life of about two hours, so nighttime dosing aligns with the body’s natural pulse of growth hormone during sleep.
Semaglutide (for weight management): This GLP-1 peptide follows a slow titration schedule. The starting dose is 0.25 mg injected once per week for four weeks, with your prescriber increasing the dose every four weeks. Jumping ahead on the schedule is one of the most common causes of side effects, which can include severe nausea, vomiting, abdominal pain, and in rare cases, pancreatitis. The FDA has specifically warned about dosing errors with compounded semaglutide products.
How Reconstitution Changes Your Math
Most injectable peptides arrive as a freeze-dried powder in a small vial. Before you can inject anything, you need to add a liquid (usually bacteriostatic water) to dissolve the powder. The volume of water you add determines the concentration of every dose you draw.
The formula is straightforward: divide the total peptide amount in the vial by the volume of water you add. If you have a 5 mg vial and add 2.5 mL of bacteriostatic water, you get a concentration of 2 mg per mL. If you add 5 mL instead, the concentration drops to 1 mg per mL. A 10 mg vial reconstituted with 5 mL gives you 2 mg per mL.
This matters because a small error in water volume creates a proportional error in every single dose you pull from that vial. Adding half the intended water doubles the concentration, meaning you’d inject twice your target dose with the same syringe volume. Write down your reconstitution math and keep it with the vial.
Reading an Insulin Syringe
Most people draw peptide doses with a standard U-100 insulin syringe. The markings on these syringes are in “units,” which correspond to volume in a simple way: 100 units equals 1.0 mL, 50 units equals 0.50 mL, and 10 units equals 0.10 mL. Each small tick mark on a 1 mL syringe represents 2 units, or 0.02 mL.
To figure out how many units to draw, you need to know the concentration you created during reconstitution. Say you have BPC-157 at a concentration of 2,500 mcg per mL (a 5 mg vial reconstituted with 2 mL of water), and your target dose is 250 mcg. That’s one-tenth of a milliliter, or 10 units on an insulin syringe. If you reconstituted the same vial with 1 mL instead, each 10-unit draw would deliver 500 mcg, double the intended amount.
Smaller syringes (0.3 mL or 0.5 mL) have finer tick marks and make it easier to measure tiny volumes accurately. If your dose works out to something like 5 units, a 0.3 mL syringe is much more forgiving than a full 1 mL syringe where the markings are spaced further apart.
Timing Around Food
Peptides that stimulate growth hormone release, like ipamorelin and CJC-1295, are best injected on an empty stomach. Growth hormone secretion is blunted by elevated blood sugar and insulin, so eating before an injection reduces its effectiveness. A general rule is to avoid food for at least two hours before and 30 minutes after injecting growth hormone peptides.
Semaglutide and other GLP-1 peptides don’t need to be timed around meals the same way. They’re injected once weekly at any time of day, regardless of food intake. Their mechanism works by slowing gastric emptying and acting on appetite-regulating pathways in the brain over a sustained period, so meal timing on injection day doesn’t meaningfully change their effect.
BPC-157 and TB-500 are not heavily influenced by food timing either, though some users prefer to inject BPC-157 on an empty stomach based on general absorption logic. There’s no strong clinical data mandating fasted injection for these recovery peptides.
Storage After Reconstitution
Once you add water to a peptide vial, the clock starts ticking. Peptide solutions are generally stable for up to one week when refrigerated at around 4°C (39°F). That’s a much shorter window than people expect, and it’s why proper storage matters.
If you won’t use the entire vial within a week, freeze individual doses in separate containers. Using sterile buffers at a pH of 5 to 6 and storing at minus 20°C or colder is optimal for extending shelf life. Peptides containing certain amino acids (asparagine, glutamine, cysteine, methionine, and tryptophan) are particularly unstable in solution and degrade faster at room temperature or at a pH above 8.
Unreconstituted peptide powder is far more stable. Kept sealed, dry, and frozen, it can last months. Once you mix it, keep it refrigerated between uses, avoid shaking the vial (swirl gently instead), and discard any solution that looks cloudy or has visible particles.
Signs You’re Dosing Too High
Side effects from peptide overdosing vary by compound but tend to follow predictable patterns. With semaglutide and other GLP-1 peptides, the most common sign of too-rapid dose escalation is intense nausea, vomiting, and abdominal pain. More serious complications from overdosing include severe low blood sugar, dehydration from persistent vomiting, and in rare cases, acute pancreatitis or gallstones.
Growth hormone peptides at excessive doses can cause water retention, joint stiffness, tingling or numbness in the hands, and headaches. These symptoms typically resolve within a day or two of reducing the dose.
BPC-157 and TB-500 have milder side effect profiles at typical doses, but injection site reactions like redness, swelling, or a small lump under the skin are common across all injectable peptides. Rotating injection sites helps minimize this. If you notice a hard, painful knot that doesn’t resolve within a few days, or any signs of infection like warmth and spreading redness, that warrants attention.
Starting at the low end of any dosing range and increasing gradually is the most reliable way to find the dose that works for you without overshooting into side effects.