Toxicology & Poisoning
Every toxicology & poisoning calculator on CalcEngines — unit converters, derived indices and interpretive tools, each with its formula, a worked example and the reference intervals it is judged against.
34 calculators in this section
- Acetoacetate Unit ConverterConvert acetoacetate between mg/dL, mg/L and mmol/L — the ketone that nitroprusside sticks actually measure, and the minority species in exactly the patients who are sickest.
- Acetone Unit ConverterConvert acetone between mg/dL, mg/L and mmol/L — the ketone that is not an acid, the metabolite of isopropanol, and the substance a nitroprusside ketone stick is actually detecting.
- Blood Alcohol Concentration (Widmark) CalculatorEstimate a blood alcohol concentration from drinks using the Widmark equation — and see the published range around that estimate, which on this page's own default inputs is wide enough to straddle two legal limits at once. This cannot tell anyone whether they are fit or legal to drive.
- Blood Alcohol Unit ConverterConvert blood ethanol between mg/dL, mg/L, g/L, g/dL and mmol/L, and see why a clinical serum result is not the same figure as a forensic whole-blood one.
- Blood Arsenic Unit ConverterConvert whole blood arsenic between µg/L, ng/mL, µg/dL, nmol/L and µmol/L. Blood arsenic has a half-life of hours and goes undetectable about two days after exposure, which is why urine is the test an occupational physician orders.
- Blood Chromium Unit ConverterConvert whole blood chromium between µg/L, ng/mL, nmol/L and µmol/L. Most people having this test have a metal-on-metal hip, and the MHRA action level of 7 ppb is nothing like an occupational exposure limit.
- Blood Cobalt Unit ConverterConvert whole blood cobalt between µg/L, ng/mL, nmol/L and µmol/L. The reference intervals from two major laboratories differ nearly fourfold, and the MHRA arthroplasty action level of 7 ppb is above both of them.
- Blood Cyanide Unit ConverterConvert whole blood cyanide between mg/L, µg/mL, µg/L and µmol/L. The factor depends on whether the measurand is the cyanide ion or hydrogen cyanide, and the two are 3.9% apart; the published laboratory pairs settle it for the ion.
- Blood Manganese Unit ConverterConvert whole blood manganese between µg/L, ng/mL, nmol/L and µmol/L. Manganese is the one metal here that is also an essential nutrient, which is why the test is ordered as often for parenteral nutrition as for an occupational exposure.
- Carbon Monoxide Poisoning InterpreterRead a carboxyhaemoglobin level against the clinical features, the exposure context and whether oxygen was given before the sample — starting from the fact that pulse oximetry reads falsely normal in carbon monoxide poisoning and cannot detect it at all.
- Carboxyhaemoglobin (COHb) InterpreterBand a co-oximetry carboxyhaemoglobin percentage from a non-smoker's baseline to a life-threatening level, and see why the number tracks the clinical picture so poorly.
- Digoxin Immune Fab Dose CalculatorWork out the number of digoxin immune Fab vials from a serum concentration or from a known ingested amount, with the empiric doses alongside — and the reason the serum digoxin becomes uninterpretable afterwards.
- Digoxin Level InterpreterBand a serum digoxin concentration from subtherapeutic through to the thresholds for digoxin-specific antibody fragments, and see why toxicity remains a clinical diagnosis.
- Ethylene Glycol Unit ConverterConvert ethylene glycol between mg/dL, mg/L and mmol/L — and read the result knowing that glycolic and oxalic acid, not the glycol, cause the acidosis and the renal failure, so a falling level can mean the damage is being done rather than averted.
- Fomepizole Dose CalculatorWork out a single fomepizole dose in milligrams from body weight and the step of the schedule — 15 mg/kg to load, 10 mg/kg for four doses, then 15 mg/kg — and see why the frequency goes up during haemodialysis.
- Iron Toxicity Dose CalculatorConvert a number of iron tablets into ingested elemental iron per kilogram against the 20 and 60 mg/kg thresholds, and avoid the salt-versus-elemental error that understates every dose.
- Isopropanol Unit ConverterConvert isopropanol between mg/dL, mg/L and mmol/L — and note the exception that makes this alcohol different: it is metabolised to acetone, which is a ketone and not an acid, so isopropanol causes ketosis without acidosis.
- Lithium Level InterpreterBand a 12-hour post-dose serum lithium from subtherapeutic to severe toxicity, and see why the number matters less than whether the exposure is acute or chronic.
- Methaemoglobin InterpreterBand a co-oximetry methaemoglobin percentage against the thresholds for cyanosis, symptoms and methylene blue, and see why the pulse oximeter sticks near 85%.
- Methanol Unit ConverterConvert methanol between mg/dL, mg/L and mmol/L — and read the result knowing that methanol itself is not what blinds people. Formic acid is, so a falling level in an acidotic patient is the worst result on the page, not the best.
- Methylene Blue Dose CalculatorCalculate a 1 or 2 mg/kg intravenous methylene blue dose for methaemoglobinaemia, with the volume of 1% solution, the repeat interval and the cumulative ceiling.
- N-Acetylcysteine Dose CalculatorWork out the total intravenous acetylcysteine dose for the standard three-bag 21-hour regimen, with each bag's dose, diluent volume and infusion time, and the reasons an infusion reaction is not a reason to stop.
- Osmolal Gap CalculatorCalculate the osmolal gap from measured osmolality, sodium, glucose, urea nitrogen and ethanol, and see why a normal gap does not exclude a toxic alcohol.
- Paracetamol (Acetaminophen) Unit ConverterParacetamol and acetaminophen are the same drug, and this converts a plasma concentration between mg/L, µg/mL, µmol/L and mg/dL. The reason to do it here is that the nomogram takes mg/L: a result in µmol/L has to be converted before it can be plotted, and the conversion reproduces the published treatment lines exactly.
- Paracetamol Toxic Dose CalculatorConvert a reported paracetamol ingestion into mg/kg against the 200 mg/kg or 150 mg/kg risk-assessment threshold, and see why the absolute dose matters as much as the weight-based figure.
- Rumack-Matthew Nomogram CalculatorPlot a paracetamol concentration against the 150 mg/L or the United Kingdom's 100 mg/L treatment line between 4 and 24 hours after a single acute ingestion, and see when the nomogram does not apply at all.
- Salicylate Toxicity Severity InterpreterRead a salicylate concentration against the arterial pH, the mental state and the kidney function the way EXTRIP and the AACT guidance do — and see why the Done nomogram, still reproduced everywhere, was validated at a predictive index of 0.42 and should not be used.
- Salicylate Unit ConverterConvert a salicylate concentration between mg/L, µmol/L, mg/dL and mmol/L — and read the number the way a toxicologist does, which is never on its own.
- Serotonin Syndrome Hunter Criteria CalculatorApply the Hunter Serotonin Toxicity Criteria as the branching decision rule Dunkley published — five independent branches, no points to add — with its 84% sensitivity against a clinical toxicologist's diagnosis and the rigidity pattern that separates it from neuroleptic malignant syndrome.
- Serum Aluminium Unit ConverterConvert serum aluminium between µg/L, ng/mL, µmol/L and nmol/L. This is a dialysis and parenteral-nutrition test, UK laboratories report it in µmol/L and US laboratories in ng/mL, and contamination at collection is the dominant error.
- Toxic Alcohol Level from Osmolal GapEstimate a methanol, ethylene glycol, isopropanol, acetone or propylene glycol concentration from the osmolal gap while a direct assay is awaited.
- Toxidrome IdentifierMap pupils, skin, bowel sounds, temperature, mental state, heart rate and the neuromuscular findings onto the classic toxidromes — built around the one discriminator that does the most work at the bedside, which is whether the skin is dry or wet.
- Urine Arsenic Unit ConverterConvert urine arsenic between µg/L, ng/mL, µg/dL, nmol/L and µmol/L — and find out why a TOTAL urine arsenic raised a day after a shellfish meal is the commonest false positive in occupational medicine.
- Urine Thallium Unit ConverterConvert urine thallium between µg/L, ng/mL, nmol/L and µmol/L. Thallium poisoning is rare, acute and often forensic, and for most hospitals the assay is a send-away to a reference laboratory.