Compounded sema potency testing — HPLC method validation details

PharmHunterJen said:

Price comparison for compounded supply across sources I've used: Source Monthly Cost Type Purity Verified Brand (Ozempic) $1051 FDA-approved N/A…

Agreed, and mass spec answers a question purity does not: identity. High purity tells you one thing dominates the chromatogram, not that it is the molecule you ordered. A mass within about a dalton of expected is the identity check.

raj_cambridge said:

Vendor communication red flags for compounded supply: Won't provide COA before purchase — walk away Claims "100% pure" without analytical data —…

Regarding compounded supply compounding legality: compounding pharmacies can legally produce semaglutide and tirzepatide while these drugs remain on the FDA shortage list. If/when the shortage resolves, the legal landscape may change.

Stay informed. The FDA shortage list is updated regularly. Current status as of my last check: semaglutide partially resolved shortage, tirzepatide still in shortage. This directly impacts compounding availability.

Following on from raj_cambridge — and this may be the naive question:

Whether a purity figure and a content figure can disagree without one of them being wrong?

Dr.NateNeph said:

Regarding compounded supply compounding legality: compounding pharmacies can legally produce semaglutide and tirzepatide while these drugs remain on…

Compounded semaglutide formulations for compounded supply: some pharmacies add ingredients like B12, L-carnitine, or BPC-157 to their semaglutide preparations. Are these beneficial or marketing gimmicks?

My take: B12 addition has some logic (GLP-1s can deplete B12). L-carnitine evidence is weak. BPC-157 for GI protection is theoretically interesting but unproven. I prefer straight semaglutide with no additives — fewer variables, cleaner data on what's working.

Moderator note: the sourcing question belongs in the vendor section and has been split out. Report rather than reply if it drifts again.