BAC Water vs Sterile Water for Peptides
A practical guide to what people commonly mix with each peptide and why. Use the recommender for a quick answer, compare the diluents side by side, then check the per-peptide table.
BAC water for multi-dose
Bacteriostatic water contains benzyl alcohol, which limits bacterial growth so a vial keeps for weeks of repeated use.
Sterile water for single use
No preservative — best for a single dose, label-specific products, or benzyl-alcohol sensitivity. Use promptly.
Labeling wins
Manufacturer and pharmacy instructions always take precedence over generic community guidance.
Common choice
BAC water
~2–4 weeks (fridge)
Multi-dose vial used daily over weeks — a preservative keeps it usable.
BAC vs sterile vs saline
| Diluent | Preservative | Use | Shelf life after mixing | Best for |
|---|---|---|---|---|
| Bacteriostatic (BAC) water | Yes — 0.9% benzyl alcohol | Multi-use | ~28 days refrigerated (varies) | Multi-dose vials used over days to weeks |
| Sterile water for injection | No preservative | Single-use (discard promptly) | Use immediately / same session | Single doses, label-specific products, benzyl-alcohol sensitivity |
| 0.9% Sodium chloride (normal saline) | Usually none (bacteriostatic saline has benzyl alcohol) | Single-use (plain) / multi-use (bacteriostatic) | Plain: use promptly | When isotonic diluent is preferred or labeled |
What people commonly mix with each peptide
| Peptide | Category | Common choice | Why | Practical window |
|---|---|---|---|---|
| BPC-157 | Healing & Recovery | BAC water | Multi-dose vial used daily over weeks — a preservative keeps it usable. | ~2–4 weeks (fridge) |
| TB-500 (Thymosin β4) | Healing & Recovery | BAC water | Dosed across a multi-week cycle from one vial. | ~2–4 weeks (fridge) |
| KPV | Healing & Recovery | BAC water | Repeated small doses from a shared vial. | ~4 weeks (fridge) |
| GHK-Cu | Cosmetic & Skin | BAC water | Stable and typically used over an extended window. | ~4 weeks (fridge) |
| CJC-1295 (with DAC) | GH Secretagogue | BAC water | Weekly dosing from one vial benefits from a preservative. | ~4 weeks (fridge) |
| CJC-1295 (No-DAC) | GH Secretagogue | BAC water | Frequent multi-dose use; keep it in a preserved solution. | ~2–4 weeks (fridge) |
| Ipamorelin | GH Secretagogue | BAC water | Multiple doses per day over weeks. | ~4 weeks (fridge) |
| Sermorelin | GH Secretagogue | BAC water | Daily multi-dose use, but shorter stability — check labeling. | ~2 weeks (fridge) |
| Tesamorelin | GH Secretagogue | Sterile water | Label-specific product; often reconstituted sterile and used quickly. | short — follow label |
| Semaglutide | GLP-1 & Metabolic | BAC water | Weekly dosing from a multi-use vial. | ~4–8 weeks (fridge) |
| Tirzepatide | GLP-1 & Metabolic | BAC water | Weekly multi-dose vial. | ~4–8 weeks (fridge) |
| Retatrutide | GLP-1 & Metabolic | BAC water | Weekly dosing over a cycle. | ~4 weeks (fridge) |
| PT-141 (Bremelanotide) | Sexual Health | BAC water | As-needed dosing from a stored vial. | ~4–8 weeks (fridge) |
| Melanotan II | Tanning | BAC water | Titrated multi-dose use over weeks. | ~4–8 weeks (fridge) |
| Oxytocin | Hormone | Sterile water | Label-specific; preservative-free preparation is common. | short — follow label |
| Kisspeptin | Fertility | BAC water | Repeat dosing from one vial. | ~4 weeks (fridge) |
| MOTS-c | Longevity | BAC water | Weekly multi-dose cycle. | ~4 weeks (fridge) |
| Epithalon | Longevity | BAC water | Short daily cycles from a shared vial. | ~2–4 weeks (fridge) |
| Thymosin Alpha-1 | Immune | Context-dependent | Some labels specify sterile; BAC is common for multi-dose. Follow the label. | check labeling |
| Glutathione | Antioxidant | Sterile water | Often single-use and light-sensitive; short window after mixing. | ~7–14 days, protect from light |
| Selank | Nootropic | Context-dependent | Route matters (intranasal vs injection) and supplier guidance varies. | depends on route |
| Semax | Nootropic | Context-dependent | Intranasal preparations differ from injectable; follow supplier notes. | depends on route |
| DSIP | Sleep | Context-dependent | Cycle length and supplier guidance drive the choice. | depends on use |
Showing 23 of 23 peptides.
Educational only
Not medical advice. Mixing guidance varies by peptide formulation, compounding standards, concentration, and labeled handling directions. Use sterile technique and follow product labeling.