The Peptide Dosing Guide: Principles, Cycles, and Per-Compound Protocols

Principles

Peptide dosing is not like dosing aspirin. The body's response varies meaningfully across individuals, the optimal dose for one peptide depends on what other peptides you're running, and most peptides have a meaningful difference between the dose that does something and the dose that does the most. These five principles should anchor every protocol:

1. Start low. Begin at the bottom of the published range. You can always increase. The body's tolerance window is wider than the effective window for most peptides — find the floor that works for you.
2. Titrate. Move dose up gradually, with a steady evaluation cadence (typically 1–2 weeks per step). For GLP-1 agonists and other peptides with steep side-effect curves, slower titration matters more.
3. Cycle. Most peptides should be used in defined cycles (8–12 weeks on, 2–4 weeks off). Indefinite use erodes receptor sensitivity for many peptides, especially GH-axis. The cycle structure also creates natural evaluation points.
4. Time to mechanism. GH-axis peptides go before bed because endogenous GH pulses during slow-wave sleep. Cognitive peptides go in the morning because that's when the activation is wanted. Sleep peptides go 30–60 min before sleep onset. Misaligned timing wastes the peptide.
5. Measure outcomes. Subjective scales (PSQI for sleep, body composition, joint pain VAS, etc.) plus appropriate labs (IGF-1, A1c, fasting insulin, lipids, etc.). Protocols without measurement are just hopes.

Route of administration

Most research peptides are not orally bioavailable in their unmodified form — the gastrointestinal tract degrades them. Effective routes include:

• Subcutaneous (SC). The default for most peptides. Inject into the fatty layer beneath the skin, commonly abdomen, thigh, or upper arm. Insulin syringe (29–31G) is standard. Bioavailability typically 70–90%.
• Intramuscular (IM). Used for some peptides like MGF where local action is desired. Faster absorption than SC but more pain.
• Intranasal. The route for Selank, Semax, DSIP, and oxytocin. Bioavailability varies (5–40%) but the convenience is high. Use a calibrated nasal spray device.
• Oral. Limited to peptides with specific protective modifications (5-Amino-1MQ orally, some KPV formulations). Most peptides don't survive the gut.
• Topical. For dermal targets (GHK-Cu, some BPC-157 formulations).
• IV. For NAD+ specifically, and certain in-clinic protocols. Requires medical setting.

Reconstitution

Most peptides arrive lyophilized (freeze-dried). To use, reconstitute with bacteriostatic water for injection (BAC water — sterile water with 0.9% benzyl alcohol added to inhibit bacterial growth). Standard protocol:

1. Bring both vial and BAC water to room temperature.
2. Wipe both stoppers with alcohol.
3. Slowly add BAC water to the peptide vial (do not spray directly onto powder — angle the needle to run water down the side).
4. Swirl gently to dissolve. Do not shake — agitation can denature peptides.
5. Store reconstituted vial at 2–8°C (refrigerated).
6. Use within 14–30 days, peptide-specific. Most stable: BPC-157, GHK-Cu, MOTS-c. Less stable: DSIP, certain GH peptides.

Volume choice matters: use enough BAC water that 1 unit on an insulin syringe equals your desired dose. Example: 5 mg of BPC-157 reconstituted in 2 ml of BAC water = 2500 mcg/ml = 25 mcg per insulin unit (assuming 1 ml = 100 units).

Cycling and receptor sensitivity

The peptides most subject to receptor downregulation with continuous use are the GH secretagogues (CJC-1295, Ipamorelin, Sermorelin). The mechanism is reduced ghrelin or GHRH receptor expression at the pituitary. The remedy is structured cycling: typically 5 nights on / 2 off weekly during a cycle, with full washouts of 2–4 weeks between 8–12 week cycles.

Other peptides have less receptor-sensitivity concern but still benefit from cycling for evaluation reasons. The BPC-157 / TB-500 recovery stack is sometimes used for indefinite low-dose maintenance, but the published research base is shorter than the timescales people are running it, so caution is warranted.

Titration

Titration matters most for peptides with steep side-effect curves. The textbook case is GLP-1 agonists: starting at 0.25 mg semaglutide weekly and increasing every 4 weeks dramatically reduces the GI side-effect burden compared to jumping in at higher doses. The general rule: if a peptide has a side-effect profile that increases with dose, titrate. If the side-effect profile is dose-independent (rare), you can start near therapeutic dose.

Timing

• Bedtime, fasted: CJC-1295, Ipamorelin, Sermorelin, Tesamorelin, DSIP, MOTS-c.
• Morning, with breakfast or fasted: Semax, Selank (first of multiple doses).
• Post-workout: IGF-1 LR3, MGF.
• Pre-event (timing-specific): PT-141 (60 min before), Melanotan II (30–90 min before).
• Anytime: BPC-157, TB-500, KPV, GHK-Cu, NAD+ (timing flexible; consistency matters more than absolute time).

Monitoring

Baseline before starting any 8+ week protocol: CBC, CMP, lipid panel, A1c, fasting insulin, IGF-1, hsCRP, cortisol AM, vitamin D, B12, ferritin. Recheck at 6 weeks for any GH-axis, GLP-1, or metabolic peptide protocol. Outside labs: subjective rating scales appropriate to the goal (PSQI for sleep, body composition for weight, joint VAS for recovery, etc.), tracked weekly during the cycle.

Safety

Universal contraindications for any peptide protocol: active malignancy, uncontrolled diabetes, pregnancy/nursing, under-18, history of severe allergic reaction to peptide carriers. Peptide-specific contraindications listed on each profile. When in doubt, get clinician guidance.

References

1. Sikiric P, et al. BPC 157 — review. Curr Pharm Des. 2018.
2. Teichman SL, et al. CJC-1295. JCEM. 2006. PMID: 16352683.
3. Wilding JPH, et al. STEP-1 (semaglutide). NEJM. 2021.
4. Yoshino J, et al. NAD+ intermediates. Cell Metab. 2018. PMID: 29551589.