Benzodiazepines
Strips plus Zimmermann confirmation. For sedation naloxone doesn’t fully reverse.
Seattle area · Nonprofit · Vendor-neutral
Harm reduction, free to anyone who asks.
My name is Robert Stewart. I do harm reduction in the Seattle area. Naloxone, safer-use supplies, education, and honest answers about what is actually in something. All of it free. No exceptions, no conditions.
- Naloxone & supplies
- Narcan and safer-use supplies, handed out at every contact
- Reagents
- Full colorimetric panel, including Marquis, Mecke, Mandelin, Simon’s, Scott’s, Zimmermann, Ehrlich and Hofmann
- Strips
- Fentanyl, benzodiazepine, xylazine, nitazene
- Cost
- Free to the public. Paid for out of pocket.
Why I source from every manufacturer
A lot of harm reduction is naloxone and supplies. The rest is being able to tell somebody what is actually in front of them. That second part is where the sourcing matters.
- Independent cross-verification. Two manufacturers’ reagents, one target, two readings. Agreement raises confidence. Disagreement means keep testing.
- Formulation coverage. Recipes and cutoffs vary by manufacturer. Different products detect different compounds.
- Supply resilience. A backorder at one manufacturer doesn’t take a test offline.
- No catalogue limits. If the right test exists, I can get it.
Standardizing on one supplier is simpler. This is a deliberate trade-off.
Testing beyond fentanyl strips
Hofmann & Ehrlich
The indole and ergoline range. Substitution is common there.
Scott’s test
A three-stage sequence. Separates cocaine from cathinones and anesthetic cuts.
Xylazine & nitazene
Neither shows on a fentanyl strip. A fentanyl-negative result isn’t conclusive.
How I process a sample
I start with what it was sold as, and whether anyone has already taken it. That sets the order.
Then a broad reagent panel — a separate portion of the sample for each reagent, read at the intervals it specifies. Class-specific chemistry for whatever the panel leaves open. Strips at the manufacturer’s dilution, not a generic one.
Anything that changes what a person does gets re-run on a second company’s product first. Then the result, in plain language, with naloxone and supplies.
What this can and can’t do
Finding fentanyl where nobody expected it is the point. That one result decides whether someone takes a substance at all — or takes it alone, with no naloxone nearby. Same for xylazine and the nitazenes. A fentanyl strip sees neither.
It doesn’t measure purity or dose. It can’t rule out every adulterant. It isn’t lab confirmation, and a negative is never an all-clear. Layering reagents, manufacturers and strips narrows the uncertainty. It doesn’t remove it, and I don’t say otherwise.
Get in touch
For manufacturers, peer organizations, and anyone who needs support.
Seattle area · Nonprofit — approval in progress
Policies
Non-discrimination
I test for everyone. Nobody is turned away over race, ethnicity, national origin, immigration status, religion, age, disability, sex, gender identity or expression, sexual orientation, housing status, income, criminal record, or what they use.
No one is asked to stop using, enter treatment, or explain themselves. Nothing I provide has conditions attached.
Privacy
This site collects nothing. No analytics, no cookies, no trackers, no forms, no third-party scripts. Fonts are served from here, not from another company. It runs on GitHub Pages, which keeps ordinary server logs like any host.
Call or text and I have your number, same as any phone call. I don’t ask for your name. I keep informal notes on what I test, never on who brought it. I don’t share what I see with police, treatment providers, or anyone else.