Clinical Tools

Answers to the question in front of you.

Four free reference tools for drug test interpretation, built from the same source documents used in ToxiPharm consulting work. No login, no paywall, and every result traceable to a cited reference.

The Tools

Each tool answers a different question that comes up when a drug test result does not look the way it should. They are free to use and intended for clinical reference, not as a substitute for confirmatory testing or professional judgment.

Tool 01
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FP / FN Checker
False Positive and False Negative Lookup

Enter a medication or substance to see which urine immunoassay panels it may interfere with. Covers 16 panels with platform-specific caveats, concentration thresholds where published, and the false negative gaps that standard panels miss. Sourced from the ToxiPharm false positive and negative reference.

16 panelsPlatform-specificCited
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Tool 02
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Detection Window Checker
Urine and Oral Fluid Windows

Search any drug or analyte to retrieve urine and oral fluid detection windows, EIA and LC-MS/MS cutoff levels, and use-pattern context. Built for the difference between a single exposure and chronic use, which is where most interpretation errors happen.

Urine & oral fluidCutoff levelsUse pattern
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Tool 03
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THC Excretion Analyst
New Use vs. Residual Excretion

Track creatinine-normalized cannabinoid levels across serial specimens to distinguish new use from residual excretion in chronic users. Applies published ratio thresholds and generates a printable clinical report. The single most common interpretation problem in cannabis monitoring.

Creatinine normalizedSerial specimensPrintable report
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Tool 04
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FAQ Reference
Searchable Clinical Q&A

A searchable reference covering specimen validity, opiates, MAT, THC isomers, stimulants, benzodiazepines, emerging substances, and oral fluid testing. Built for rapid access during a consulting call or a program review, when the answer is needed in seconds.

SearchableBy categoryRapid access
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How These Are Built
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Traceable to a source

The checkers are driven by the same reference documents used in ToxiPharm consulting work, with PMIDs and platform detail carried through to the result. Where evidence is thin, entries are flagged as unverified rather than stated plainly.

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Updated with the literature

A weekly literature scan feeds new cross-reactants, detection window data, and emerging substances back into the underlying references, and the tools are refreshed when the source documents change.

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Screening context, not a verdict

These tools identify documented possibilities. They do not confirm what happened in a specific case. Unexpected results should be confirmed by LC-MS/MS and interpreted alongside the clinical picture.

Beyond the Tools
When the result still does not add up.

These tools handle the common questions. For a contested result, a program policy review, or expert testimony, that is where a consultation makes sense.

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