ResusDocDrug Monographs

Reference material for UK healthcare professionals. Doses and licensing change — verify against the current SmPC and local policy before use.

ResusDoc

Drug Monographs

Textbook-depth, referenced articles on the drugs we actually reach for in the emergency department — the pharmacology behind them, the evidence under them, and the places they catch people out.

70 monographs · UK licensing · primary sources cited

Glutathione precursor — antidote in paracetamol poisoning

Acetylcysteine Acetylcysteine 200 mg/mL injection (NAC)

The same 300 mg/kg, delivered over 12 hours instead of 21, with a fifth of the anaphylactoid reactions. Standard UK care — though the product labels have not caught up.

AntidoteToxicologyCritical care

Adsorbent — non-specific gastrointestinal decontaminant and enhancer of elimination

Activated charcoal Carbomix · Actidose-Aqua · Charcodote

The rule everybody learned — one hour, or don't bother — has been superseded for selected poisons. The 2026 international guideline replaces it with a poison-by-poison risk assessment and a window of up to six hours.

AntidoteDecontaminationOverdose

Endogenous purine nucleoside · AV nodal blocking agent

Adenosine Adenocor

A ten-second drug that is almost always given wrongly — too slowly, too distally, and with too little warning to the patient.

CardiologyArrhythmiaSVT

Endogenous catecholamine · α and β adrenoceptor agonist

Adrenaline Epinephrine · EpiPen · Jext

The most important drug in the department, and the one whose two concentrations kill people when confused.

ResuscitationCardiac arrestAnaphylaxis

Methylxanthine — phosphodiesterase inhibitor and adenosine receptor antagonist

Aminophylline Aminophylline 25 mg/mL injection

A narrow therapeutic index, a loading dose that must be omitted if the patient is already taking it, and a niche in resuscitation almost nobody expects.

AsthmaBradycardiaResuscitation

Class III antiarrhythmic (multi-channel blocker)

Amiodarone Cordarone X

Blocks every channel it meets and damages most organs it reaches — yet remains the antiarrhythmic we give when the shocks stop working.

CardiologyArrhythmiaCardiac arrest

Recombinant modified factor Xa decoy — specific reversal agent for apixaban and rivaroxaban

Andexanet alfa Ondexxya

A decoy factor Xa that mops up apixaban and rivaroxaban. Effective, thrombogenic, expensive, and recommended by NICE for gastrointestinal bleeding only.

AntidoteReversalHaemorrhage

Antimuscarinic (competitive acetylcholine antagonist)

Atropine

Simple to dose and easy to misuse — too small a dose slows the heart, and in the blocks that matter most it does not work at all.

ResuscitationBradycardiaArrhythmia

Beta-1 selective adrenoceptor antagonist

Bisoprolol Cardicor · Emcor

Oral only, so never the answer to a tachycardia in front of you — but very often the drug you must decide what to do with.

CardiologyHeart failureAtrial fibrillation

Divalent cation — membrane stabilisation and calcium replacement

Calcium salts Calcium chloride 10% · Calcium gluconate 10%

Three UK ampoules, all called ten percent something, containing 2.23, 6.8 and 10 mmol of calcium. Getting the salt right matters more than getting the volume right.

ResuscitationElectrolytesAntidote

First-generation antihistamine with non-specific 5-HT1A and 5-HT2 antagonism

Cyproheptadine Periactin

The only thing resembling an antidote for serotonin toxicity. It is oral, unlicensed for the purpose, absent from the emc, and a 2025 review concludes its clinical effect is probably just sedation.

AntidoteSerotonin toxicityPoisoning

Water-soluble dithiol chelator; 2,3-dimercapto-1-propanesulfonate

DMPS (Unithiol)

The chelator associated with objective recovery from mercury brain injury in one documented UK case, and which no UK company sells.

AntidoteMercuryArsenic

Ryanodine receptor (RyR1) antagonist — direct skeletal muscle relaxant

Dantrolene Agilus · Dantrium IV (discontinued) · Dantrium capsules

The only drug that treats malignant hyperthermia, and the only one whose UK preparation has quietly changed in a way that invalidates the number most people memorised.

AntidoteMalignant hyperthermiaAnaesthesia

Siderophore-derived hexadentate iron chelator

Desferrioxamine Desferal

The antidote to a poisoning that looks better before it gets much worse, given to a patient whose urine tells you it is working.

AntidoteIronPoisoning

Cardiac glycoside · Na⁺/K⁺-ATPase inhibitor

Digoxin Lanoxin

Two hundred years old, still in the algorithm, and the only rate-control drug that works in a patient too unwell for the others.

CardiologyAtrial fibrillationRate control

Ovine digoxin-specific antibody fragments — antidote

Digoxin immune Fab DigiFab

The UK label divides serum digoxin by 200. The US label divides it by 100. Both are current, both are for the same product, and the difference is a factor of two in an antidote.

AntidoteToxicologyCardiology

Non-dihydropyridine calcium channel blocker (class IV)

Diltiazem Tildiem · Adizem · Slozem

The rate-control drug UK clinicians read about in American papers and cannot give intravenously — because the IV preparation does not exist here.

CardiologyAtrial fibrillationRate control

Oil-based dithiol chelator; British anti-Lewisite

Dimercaprol (BAL)

The original chelator, invented to counter a chemical weapon, now largely superseded by the analogues built to fix its faults.

AntidoteArsenicMercury

Synthetic catecholamine · β₁-predominant inotrope

Dobutamine

An inotrope, not a vasopressor — and one that can lower the blood pressure of the patient you gave it to.

ShockHeart failureCritical care

Endogenous catecholamine — dose-dependent dopaminergic, β₁ and α₁ agonist

Dopamine Dopamine hydrochloride concentrate

The vasopressor that taught a generation a dose-response model that turned out not to describe individual patients — and lost its first-line place to noradrenaline on arrhythmias.

VasopressorInotropeShock

Competitive substrate for alcohol dehydrogenase

Ethanol Dehydrated Alcohol (Absolute Alcohol) BP for Injection — discontinued

The original toxic alcohol antidote, dosed by the drinking history of the patient and titrated to a blood alcohol level. The UK product is discontinued and the regimen survives mainly as the fallback when fomepizole cannot be found.

AntidoteToxic alcoholsMethanol

Imidazole intravenous general anaesthetic — GABA-A potentiator

Etomidate Hypnomidate

The induction agent that does not drop the blood pressure, and inhibits cortisol synthesis after a single dose. Twenty years of argument have not fully settled what that costs.

RSIAirwayAnaesthesia

Synthetic phenylpiperidine opioid — μ receptor agonist

Fentanyl Sublimaze · fentanyl citrate injection

A fast, short, haemodynamically quiet opioid — whose labelled adverse effect list puts muscle rigidity, including of the chest wall, in the very common category.

RSIAnalgesiaAirway

Class Ic antiarrhythmic (sodium channel blocker)

Flecainide Tambocor

Excellent at restoring sinus rhythm in a structurally normal heart, and lethal in a scarred one. The whole drug turns on that distinction.

CardiologyArrhythmiaAtrial fibrillation

Benzodiazepine receptor antagonist

Flumazenil Anexate

A clean, effective antagonist that is nonetheless the wrong answer to most overdoses. Knowing why is more useful than knowing the dose.

AntidoteToxicologySedation

Reduced folate — bypasses dihydrofolate reductase blockade

Folinic acid Calcium folinate · Sodiofolin (disodium folinate) · (leucovorin)

The only cell-rescue antidote in routine use, dosed against a drug level rather than against the patient, and the one drug that must not be given near its own partner antidote.

AntidoteMethotrexateRescue

Competitive alcohol dehydrogenase inhibitor

Fomepizole Fomepizole Waymade

It stops the poison becoming poisonous. In the UK it is licensed to do that for antifreeze and, on the label, not for methanol.

AntidoteToxic alcoholsEthylene glycol

Pancreatic polypeptide hormone — glycogenolytic and positive inotrope

Glucagon GlucaGen · GlucaGen HypoKit

Two very different drugs share a name: 1 mg IM for the hypo in the ambulance, and a 10 mg off-label bolus for the beta-blocker overdose in resus. Only one of them is licensed.

AntidoteToxicologyEndocrine

Organic nitrate · nitric oxide donor

Glyceryl trinitrate GTN · Nitrolingual · Nitrocine

A preload reducer masquerading as a chest pain drug — which is why it transforms acute pulmonary oedema and harms the preload-dependent.

CardiologyHeart failureACS

Quaternary ammonium antimuscarinic

Glycopyrronium bromide Glycopyrrolate · Robinul

Atropine's quaternary cousin: the same vagolytic effect at the heart, with far less of the delirium, the blurred vision and the pupils.

BradycardiaAnaesthesiaRSI

Hyperinsulinaemic euglycaemic therapy (HIET) — inodilator in cardiotoxic poisoning

High-dose insulin Actrapid · Humulin S (soluble human insulin)

An inodilator, not a vasopressor. It works, it takes half an hour to do so, and giving it without noradrenaline is the commonest way to make the patient worse.

AntidoteToxicologyShock

Cobalt-containing vitamin B₁₂ precursor — direct cyanide chelator

Hydroxocobalamin Cyanokit (cyanide) · Neo-Cytamen (vitamin B₁₂ deficiency)

The cyanide antidote you can give to a hypotensive burns patient with a head injury and a normal haemoglobin, because it has no contraindications and does not make methaemoglobin.

AntidoteCyanideSmoke inhalation

Bradykinin B2 receptor antagonist

Icatibant Firazyr

The right drug for the rare angioedema, and — on the best evidence available — the wrong one for the common angioedema it keeps getting used for.

AngioedemaAirwayImmunology

Humanised monoclonal antibody Fab fragment — specific dabigatran-binding reversal agent

Idarucizumab Praxbind

The only reversal agent on the estate with no contraindications, no dose calculation and no weight band. Two vials, fixed, every time — and it is useless against every anticoagulant except one.

AntidoteReversalAnticoagulation

Non-selective β₁/β₂ adrenoceptor agonist — chronotrope

Isoprenaline Isoprenaline hydrochloride · Midomil

A chemical pacing wire with a two-minute half-life. Prepared 2 mg in 500 mL, run at 0.5–10 µg/min, and titrated to symptoms rather than to a number.

BradycardiaCardiologyResuscitation

NMDA receptor antagonist · dissociative anaesthetic

Ketamine Ketalar

The most useful drug in the department, and the one whose SmPC has drifted furthest from how it is actually used.

SedationAnalgesiaRSI

Carnitine — essential cofactor for mitochondrial fatty acid β-oxidation

Levocarnitine Levocarnitine Paediatric 30% oral solution · (Carnitor, not UK-listed)

A cofactor, not a chelator. It plausibly redirects valproate metabolism away from the toxic pathway, is close to harmless, and has never been shown in a controlled trial to help.

AntidoteValproatePoisoning

Amide local anaesthetic · class Ib antiarrhythmic

Lidocaine Xylocaine

The drug we give most often and calculate least often — and the one whose toxicity has a specific antidote most people cannot dose from memory.

Local anaesthesiaArrhythmiaCardiac arrest

Intravenous lipid emulsion — antidote in local anaesthetic systemic toxicity

Lipid emulsion Intralipid 20%

A bag of parenteral nutrition that is also the only antidote for a local anaesthetic cardiac arrest. The regimen most departments have laminated to the wall has been withdrawn.

AntidoteToxicologyResuscitation

Electrolyte · membrane stabiliser · anticonvulsant

Magnesium sulphate

Three unrelated emergencies, three different regimens, and one unit muddle that causes most of the confusion.

ResuscitationObstetricsAsthma

α₁ agonist with indirect sympathomimetic action

Metaraminol Aramine

The vasopressor you can run peripherally while someone else puts in the central line — with a mechanism that guarantees it stops working.

ShockResuscitationVasopressor

Inhaled halogenated ether analgesic

Methoxyflurane Penthrox

The green whistle. Potent, fast, patient-controlled — and carrying a nephrotoxicity history that explains every dose cap on the label.

AnalgesiaTraumaPrehospital

Thiazine dye — methaemoglobin reducing agent

Methylene blue Methylthioninium chloride Proveblue

An antidote that becomes the poison above its ceiling dose, is contraindicated in the deficiency it is most often given for, and causes serotonin syndrome with the commonest drug class in the country.

AntidoteToxicologyCritical care

Beta-1 selective adrenoceptor antagonist

Metoprolol Betaloc · Lopresor

The UK's practical intravenous beta-blocker for acute rate control — and a drug whose label still recommends something COMMIT showed causes harm.

CardiologyArrhythmiaRate control

Short-acting imidazobenzodiazepine

Midazolam Midazolam solution for injection · Buccolam (oromucosal)

Three concentrations, a dose that halves after the age of sixty, and a reversal agent you should usually not reach for.

SedationRSIAirway

Competitive opioid receptor antagonist

Naloxone Prenoxad · Nyxoid

UK emergency practice now titrates from 100 micrograms, not from 400. The endpoint is a respiratory rate above 10 — not a conversation.

AntidoteToxicologyPrehospital

Endogenous catecholamine · α₁-predominant vasopressor

Noradrenaline Norepinephrine

The first-line vasopressor in shock — and the one whose UK ampoules express strength two different ways.

ShockSepsisResuscitation

Somatostatin analogue — inhibits pancreatic insulin release

Octreotide Sandostatin · generic octreotide

The reason a sulfonylurea overdose keeps dropping its glucose is that you keep giving it glucose. Octreotide breaks that loop.

AntidoteSulfonylureaHypoglycaemia

Medicinal gas — competitive displacement of carbon monoxide from haemoglobin

Oxygen Medicinal oxygen · Entonox (as a component)

The most-given antidote in the department, and the only one nobody thinks of as a drug. For carbon monoxide it is competitive displacement — the antidote is the substrate.

AntidoteCarbon monoxideSmoke inhalation

Oral thiol chelator; degradation product of penicillin

Penicillamine

The only orally licensed heavy-metal chelator in the UK, licensed for a poisoning it is rarely the best drug for.

AntidoteLeadPoisoning

Competitive non-selective α₁ and α₂-adrenoceptor antagonist

Phentolamine Phentolamine mesilate 10 mg/mL

Now licensed again in the UK — for phaeochromocytoma. The use every ED knows it for, rescuing an extravasated noradrenaline, appears nowhere on the label.

AntidoteHypertensionToxicology

Vitamin K₁ — cofactor for γ-carboxylation of factors II, VII, IX and X

Phytomenadione Konakion MM · Konakion MM Paediatric

Cheap, slow and indispensable. It does nothing for four hours, which is why it never goes alone — and it must not go into a muscle.

AntidoteReversalHaemorrhage

Oxime — reactivator of organophosphate-inhibited acetylcholinesterase

Pralidoxime Pralidoxime mesilate (P2S) — no UK licensed product

The nicotinic half of organophosphate treatment: a plausible mechanism, a time limit measured in minutes for some agents, and a randomised trial of the WHO dose that found no benefit and a point estimate pointing towards harm.

AntidoteOrganophosphateNerve agent

Class Ia antiarrhythmic (sodium channel blocker)

Procainamide Pronestyl

Promoted to first-line for stable VT in the 2025 algorithm — and stocked by remarkably few UK departments.

CardiologyArrhythmiaVT

Antimuscarinic antiparkinsonian agent — restores dopamine–acetylcholine balance in the striatum

Procyclidine Kemadrin · Arpicolin

The drug that reverses an acute dystonic reaction in minutes — a genuinely satisfying piece of emergency medicine, now complicated by the disappearance of the only formulation that worked in a patient with a locked jaw.

AntidoteAcute dystoniaAntipsychotics

Intravenous general anaesthetic — GABA-A receptor potentiator

Propofol Propofol 1% · Diprivan

The most reliable induction agent available and the one most likely to drop the blood pressure of the patient who could least afford it.

RSIAirwayAnaesthesia

Cationic polypeptide — forms an inert ionic complex with heparin

Protamine sulfate Prosulf

A fish-sperm protein that neutralises heparin by electrostatic attraction, and kills people by being pushed in too fast. The dose falls as the clock runs.

AntidoteReversalAnticoagulation

Four-factor human plasma-derived coagulation factor concentrate (II, VII, IX, X)

Prothrombin complex concentrate Octaplex · Beriplex

Factors II, VII, IX and X in 40 mL instead of four units of plasma. It corrects the INR in minutes and wears off in hours — which is why vitamin K is not optional.

ReversalHaemorrhageBleeding

Non-absorbed ion-exchange resin; ferric hexacyanoferrate(II)

Prussian Blue

A pigment that traps thallium in the gut, chosen as the antidote of choice mainly because everything else is worse.

AntidoteThalliumPoisoning

Vitamin B₆ — precursor of pyridoxal 5′-phosphate, cofactor for glutamate decarboxylase

Pyridoxine Pyridoxine 50 mg tablets · Pabrinex (as a component)

Refractory seizures with a profound lactic acidosis in someone on tuberculosis treatment is a vitamin deficiency you can reverse in minutes — if you can find the intravenous preparation, which is not licensed in the UK.

AntidoteIsoniazidSeizures

Aminosteroid non-depolarising neuromuscular blocking agent

Rocuronium Esmeron (discontinued) · generic rocuronium bromide

One milligram per kilogram gives intubating conditions in sixty seconds. Sugammadex removed the objection that used to make people choose suxamethonium instead.

RSIAirwayAnaesthesia

Parenteral polyaminocarboxylic acid chelator (edetate calcium disodium)

Sodium Calcium Edetate

The intravenous lead chelator with the most experience behind it, one word away from a drug that causes fatal hypocalcaemia.

AntidoteLeadPoisoning

Alkalinising agent — sodium loading and pH manipulation

Sodium bicarbonate Sodium Bicarbonate 8.4% w/v

8.4% is 1 mmol per millilitre. It is a genuinely specific antidote in sodium-channel-blocker poisoning and a largely discredited reflex in everything else.

AntidoteToxicologyResuscitation

Methaemoglobin former plus sulphur donor — the two-step cyanide antidote

Sodium nitrite and sodium thiosulphate Nithiodote · Sodium Thiosulfate Solution for Injection

An antidote that deliberately poisons the haemoglobin to save the mitochondria. It works, and it has killed at less than twice the therapeutic dose.

AntidoteCyanidePoisoning

Oral dithiol chelator; meso-2,3-dimercaptosuccinic acid

Succimer (DMSA)

The oral lead chelator with no demonstrated disadvantage against the intravenous one, and which no UK company sells.

AntidoteLeadPoisoning

Modified γ-cyclodextrin selective relaxant binding agent

Sugammadex Bridion

Encapsulates rocuronium and reverses paralysis in minutes. What it cannot do is give an apnoeic patient somewhere to breathe.

AirwayRSIAnaesthesia

Depolarising neuromuscular blocking agent

Suxamethonium Suxamethonium chloride · succinylcholine

The fastest onset and shortest duration of any paralytic, and a contraindication list that reads like a description of the emergency department's caseload.

RSIAirwayAnaesthesia

Antifibrinolytic · lysine analogue

Tranexamic acid Cyklokapron

Cheap, stable and genuinely life-saving in the right bleed — and clearly not a general-purpose haemostatic, as HALT-IT settled.

TraumaHaemorrhageObstetrics

Vasopressin V1/V2 receptor agonist — non-catecholamine vasopressor

Vasopressin Argipressin

A vasopressor that works when catecholamines have stopped working — and whose UK licence mentions neither shock nor cardiac arrest.

VasopressorShockCritical care

Non-dihydropyridine calcium channel blocker (class IV)

Verapamil Securon · Isoptin

Effective, cheap and unforgiving. Two specific errors with verapamil kill patients, and both are avoidable at the bedside.

CardiologyArrhythmiaSVT