Peptide Stack Planner: Synergistic Protocols & Cycle Tracking

How to Use This Planner

1. 1Build your stack. Each row is one compound. Select a compound from the dropdown — dose and frequency auto-fill with standard defaults. Adjust as needed. Add up to 8 compounds with the "+ Add compound" button.
2. 2Set cycle length. Enter the number of weeks (default: 12). Optionally add a start date to see real calendar dates in the schedule below.
3. 3Review warnings. The conflict detector flags combinations that are not clinically standard — such as two GLP-1 agonists, or more than two GH secretagogues. Address warnings before finalizing a protocol.
4. 4Copy your protocol. Click "Copy protocol" to get a formatted plain-text summary with all compounds, doses, frequencies, and half-lives — ready to paste into notes or share with a healthcare provider.

Your Stack Schedule

The calendar below updates live as you modify the stack. Each injection event is colour-coded by compound. For compounds dosed every two weeks (CJC-1295 DAC), events appear on alternating weeks. Scroll horizontally on mobile if your stack has many compounds.

The Science of Peptide Stacking

Peptide stacking works because the body's signalling systems are modular. Different receptor classes operate largely independently — activating one does not saturate or block another in a different system. A GLP-1 receptor agonist occupies GLP-1R on L-cells and vagal afferents. A GHRH analog (CJC-1295) binds GHRHR on anterior pituitary somatotrophs. A GHRP like Ipamorelin binds GHS-R1a on the same somatotrophs. BPC-157 acts via VEGF receptor upregulation and NO pathways in peripheral tissue. These four mechanisms can run simultaneously without pharmacological interference — each pathway contributes its effect independently.

The result is synergy through orthogonality: the combined outcome exceeds what any single compound achieves, not because the drugs enhance each other's receptor binding, but because they target distinct physiological levers that collectively produce an outcome impossible to achieve with one compound. Fat loss (GLP-1R), GH pulse amplification (GHRHR + GHS-R1a), and tissue repair (VEGF/NO) operating simultaneously create a body-composition and recovery environment that no single agent can replicate.

Receptor Competition: When Stacking Goes Wrong

Not all combinations are orthogonal. Within the same receptor class, competition is real and additive benefit is lost. The two clearest examples:

• Two GLP-1 agonists (tirzepatide + semaglutide): Both compete for GLP-1R occupancy. At therapeutic doses, a single GLP-1 agonist achieves near-maximal receptor activation — adding a second provides no incremental GLP-1R signal and doubles GI side-effect burden. The conflict detector flags this.
• Three or more GH secretagogues: Adding a third compound to a GHRH + GHRP stack (e.g., CJC-1295 + Ipamorelin + GHRP-2 + MK-677) does not meaningfully amplify GH pulse amplitude beyond a well-chosen two-compound combination, but does increase systemic GH axis suppression, water retention, and cortisol co-stimulation risk.

Half-Life Alignment and the Coverage Window

Another key stacking principle is matching half-lives to your pharmacokinetic goals. Short-acting peptides (t½ under 4 hours: Ipamorelin, CJC-1295 no DAC, BPC-157) require multiple daily doses to maintain tissue-level exposure. Long-acting compounds (t½ over 24 hours: Semaglutide 168 h, CJC-1295 DAC 192 h, Testosterone Enanthate 108 h) establish sustained plasma coverage with once-weekly or less frequent dosing. Mixing both creates a "base + pulse" architecture: the long-acting compound provides continuous receptor activation while the short-acting compound creates timed, amplified pulses. The classic example is CJC-1295 DAC as a sustained GHRH base with pulsatile Ipamorelin co-injections on training days.

Popular Stacks Explained

Safety, Receptor Downregulation & Off-Cycle Planning

The most common mistake in peptide stacking is treating GH secretagogues as indefinitely sustainable daily compounds. They are not. GHS-R1a (the ghrelin receptor on pituitary somatotrophs, targeted by Ipamorelin, GHRP-2, and GHRP-6) undergoes measurable desensitization with continuous agonism — a process driven by receptor internalization and β-arrestin-2 recruitment that reduces surface receptor density over weeks of continuous use.

The clinical correlate: after 8–12 weeks of uninterrupted daily GHRP use, users typically report diminishing GH pulse amplitude — the injection feels less effective. A 4-week complete cessation allows GHS-R1a resensitization (receptor recycling back to the cell surface), restoring full response at the start of the next cycle. This is not a theoretical concern — it is one of the most reproducible observations in the research peptide community.

Peptide Half-Life & Protocol Reference

The following table covers all 24 compounds available in the stack planner. Half-life data is sourced from published pharmacokinetic studies and FDA prescribing information where available; research-peptide values are derived from peer-reviewed pharmacology literature.

Frequently Asked Questions

This planner is for educational and research reference only. Peptide compounds listed (BPC-157, TB-500, Ipamorelin, CJC-1295, etc.) are not FDA-approved for human therapeutic use. GLP-1 agonists are prescription drugs — use only under medical supervision. Conflict warnings are based on general pharmacological principles and are not exhaustive. Half-life data sourced from published PK studies. Not medical advice. Methodology