Raww
Member
You know what - that makes sense. The name brand ones are single dose injectors. So unless you plan on using your whole vial in one shot - chatgtp might be on to something...Agreed but a few PE forums advise AA water as does ChatGPT.
I appreciate u taking the time to search and trying to help out though
Grok says this, btw:
Alprostadil for injection (the active ingredient in Caverject, Edex, Trimix/Quadmix/Bimix compoundscan be reconstituted with two different types of water, and the choice matters a lot for comfort, stability, and how long the vial stays usable.
### Bacteriostatic Water (BW or “Bac Water”)
- Contains 0.9–1% benzyl alcohol as a preservative
- What the FDA-approved brand-name products (Caverject, Caverject Impulse, Edex) all use
- Slightly less painful on injection because benzyl alcohol is a mild local anesthetic
- Officially approved for multi-dose use (the package insert says the reconstituted vial is good for 24 hours at room temperature, but many clinics and the manufacturer’s own stability data allow refrigerated storage for weeks)
- Downside: benzyl alcohol can, over weeks/months, slowly degrade prostaglandins (alprostadil is a prostaglandin E1). In practice this is rarely a very slow process when refrigerated, and most men finish a 5–20 µg vial long before significant potency loss occurs.
### Sterile Water with Acetic Acid 0.6% (“AA Water” or “Prostaglandin Reconstitution Solution”)
- Sold by many 503A/503B compounding pharmacies specifically for Trimix, Bimix, Quadmix
- Contains a tiny amount of acetic acid (vinegar) to drop the pH to ~4, which dramatically improves alprostadil stability
- No benzyl alcohol → no slow degradation of the prostaglandin
- Pharmacies that ship Trimix nationwide almost always use this because vials routinely last 3–6 months frozen and 30–90 days refrigerated with essentially zero potency loss
- Downside: the acetic acid makes the injection sting/burn noticeably more than bacteriostatic water for most men (some describe it as “hot” or “burning” for 30–60 seconds). A few guys don’t notice any difference, but the majority do.
### Why the difference in recommendations?
- Brand-name manufacturers (Pfizer, Schwarz Pharma/Endo) only tested and got FDA approval with bacteriostatic water, so that’s what they have to tell you to use.
- Compounding pharmacies and men who compound their own (or use “research” alprostadil) want maximum shelf life and rock-solid potency 3–6 months later, so they switched to the acetic-acid version years ago and have stability data showing it’s vastly superior for long-term storage.
### Practical advice most experienced users and urologists follow
- If you are using an official Caverject/Edex kit → just use the diluent they give you (it’s bacteriostatic water). You’ll finish the vial in a few weeks anyway.
- If you are using compounding-pharmacy Trimix/Quadmix/Bimix or raw alprostadil powder → most people use the acetic-acid water the pharmacy provides because the vial will last 3–6 months with no measurable loss of strength. Accept the extra sting or…
- Some guys who are very pain-sensitive ask the compounding pharmacy to reconstitute with bacteriostatic water instead (many pharmacies will do it on request). You trade a little shelf life for much less burn.
Bottom line
“Bac water” = less pain, perfectly fine shelf life for most people, required for FDA-approved products.
“AA water” = more sting, but near-perfect long-term stability, standard in the compounding world.
Choose based on how long you need the vial to last and how sensitive you are to injection-site burn.
