I keep seeing people mention sending their compounded meds to "Janoshik" for testing but I have no idea how to actually do it. Can someone walk me through the process? How much does it cost? How long does it take? What do I need to send?

I just got a new batch of compounded semaglutide and I want to verify it before I start using it. First time doing this. 🔬

I've sent 6 samples to Janoshik over the past year so I've got this down to a science (pun intended). Here's the complete walkthrough:

WHAT IS JANOSHIK?

Janoshik Analytical is an independent testing laboratory based in the Czech Republic that specializes in testing pharmaceuticals, peptides, and related compounds. They're popular in the peptide community because they're independent (no ties to vendors or pharmacies), affordable, and have a solid track record.

WHAT TESTS DO THEY OFFER FOR PEPTIDES?

• Identity confirmation — verifies the substance is actually what it claims to be
• Purity/Potency (HPLC) — measures the percentage of active ingredient
• Concentration — verifies mg/mL matches the label claim
• Endotoxin testing (LAL) — checks for bacterial endotoxins (important for injectables)
• Sterility testing — checks for microbial contamination

PRICING (as of early 2026):

• Basic identity + purity: ~$80-100
• Full panel (identity + purity + endotoxin): ~$120-150
• With sterility: add ~$50-80

Prices vary slightly so check their current listing.

HOW TO SUBMIT A SAMPLE — STEP BY STEP:

1. Contact Janoshik — email them or use their website contact form. Describe what you're sending (compounded semaglutide, X mg/mL, liquid or lyophilized) and what tests you want.
2. They'll respond with shipping instructions, a sample ID number, and payment details.
3. Prepare your sample:
   • For liquid: they typically need 0.3-0.5mL. Draw this amount into a sterile syringe and cap it, OR send a portion of the vial.
   • For lyophilized: send the entire vial if possible (they'll use a portion and can return the rest).
   • If you want to keep using your vial, draw the sample amount first, then use the rest normally.
4. Package it properly:
   • Wrap the vial/syringe in bubble wrap
   • Include cold packs if shipping liquid (especially in warm weather)
   • Use an insulated mailer or small insulated box
   • Include a note with your sample ID, your name/email, and what tests you want
5. Ship via international express courier — DHL or FedEx International Priority are the most reliable to Czech Republic. Expect $40-70 for shipping depending on your location.
6. Pay — they accept various payment methods. Pay when they confirm receipt of your sample.
7. Wait — turnaround is typically 5-10 business days after they receive the sample.
8. Results — they email you a detailed report with all test results, including chromatograms.

This is incredibly detailed, thank you. A few questions:

1. If I draw 0.5mL from my vial for testing, do I need to adjust my remaining dose calculations?
2. Is it legal to ship pharmaceuticals internationally like this?
3. Can I trust a lab in the Czech Republic? How do I know THEY'RE legit?

Good questions:

1. Yes — if you started with 2mL and drew 0.5mL for testing, you now have 1.5mL. Adjust your dose count accordingly. Simple math.

2. You're sending a small sample for analytical testing, not importing/exporting drugs for distribution. In practice, small quantities for personal testing purposes ship internationally without issues. I've never had a shipment stopped by customs in 6 attempts. That said, label it accurately on the customs form — "pharmaceutical sample for laboratory analysis."

3. Fair question. Janoshik has been operating since around 2015 and has tested thousands of samples. They've built their reputation in the bodybuilding and peptide communities through consistent, accurate results. Multiple users on this forum and others have sent duplicate samples to Janoshik AND to domestic US labs and gotten concordant results. They're not ISO 17025 accredited (which is a legitimate criticism), but their methodology is solid — they use HPLC-UV and HPLC-MS on calibrated instruments.

Are there US-based alternatives? Yes — some people use domestic labs, but they tend to be more expensive and some won't accept samples from individuals (only from businesses).