Dr.NutriCornell said:

Prices dramatically below market are the strongest single signal, and the reason is arithmetic rather than suspicion.

Genuinely useful, thank you. I had the facts and not the framework. Printing the relevant bit and taking it with me.

Clinical perspective, offered as context rather than as advice.

Shipping damage protocol for vendor vetting orders: if your package arrives with visible damage, temperature excursion, or broken vials:

• Photograph EVERYTHING before discarding packaging
• Note the temperature of the cold pack (liquid = possibly too warm)
• Contact the vendor within 24 hours with photos
• Request a replacement shipment or refund
• Do NOT use potentially compromised medication

Reputable vendors will replace damaged shipments without argument. If they push back, that's a red flag about the vendor.

PharmD_Rodriguez said:

The provenance questions are more useful than the numbers.

I am more sceptical of certificates as a category than this thread is. The document tells you about a sample somebody chose to send, at a moment in time, and nothing about the vial in your hand. Independent purchase-and-test is a different quality of evidence and everything else is inference.

Worth separating that from certificates of analysis, which this thread keeps folding into the same question. They behave differently and the advice does not transfer.

alex_tucson said:

The pattern that distinguishes a bad batch from an exit is behaviour rather than product.

Vendor reputation tracking for vendor vetting: I maintain a personal spreadsheet with every order I've placed — date, vendor, batch number, Janoshik result, personal efficacy assessment (1-5 scale), and any issues.

After 23 orders across 5 vendors: average purity 98.3%, zero sterility concerns, 0 shipping issues (all resolved). This data gives me confidence in my current source and documentation if issues arise.

I encourage everyone to track their orders systematically. Community data aggregation makes us all safer.

Moderator note: reminder that nothing in this thread is medical advice, and that clinical claims need a source. No action needed from anybody.