Activated Charcoal
CLASS
- decontamination agent
MECHANISM OF ACTION
- adsorbs molecules of drug on its surface, which inhibits their absorption by as much as 50% and leads to their excretion in faeces
- absorptive area = 3,000 m2/g
PHARMACEUTICS
- odourless, tasteless, fine black powder
- chemically inert form of carbon prepared by pyrolysis of carbonaceous matter (coconut, pulverised peat or sawdust) at 600-900 C in a kiln without air.
- then concentrated with zinc chloride solution, washed off with dilute acid & water, and exposed to steam or CO2 at 600-700 C that forms an internal maze of pores.
DOSE
- 1g/kg
- 50g in 100mL
- should be given within 1 h
- can be given later dependent on characteristics of the ingested agent, for instance may be appropriate if the drug:
- is not lipid soluble
- has slow passage to intestine
- is a sustained release preparation, and/or
- ingested with other agents that slow gastrointestinal absorption of durgs (e.g. anticholinergics)
INDICATIONS
- Used for decontamination of the gastrointestinal tract following ingestion of a potentially toxic agent
- give if toxic agent is still within the gastrointestinal tract (e.g. within 1 hour) and potential benefits out weigh risks.
- Useful in overdose from:
- aspirin
- paracetamol
- barbiturates
- TCA’s
- digoxin
- amphetamines
- morphine
- cocaine
- phenothiazines
Multi-dose activated charcoal can be used in selected cases for decontamination (e.g. where absorption is greatly delayed) or enhanced elimination (e.g. where there ther is entero-hepatic circulation) (see enhanced elimination)
ADVERSE EVENTS
- vomiting
- pulmonary aspiration
- direct administration to lung via N/G tube -> potentially fatal
- impaired absorption of oral medications/antidotes
- corneal abrasions
- constipation/bowel obstruction
PHARMACOKINETICS
- Absorption
- Distribution
- Metabolism
- Elimination
EVIDENCE
- single dose activated charcoal is generally the preferred method of decontamination but does not improve outcome when applied to unselected patients
References and Links
CCC Pharmacology Series
Respiratory: Bosentan, Delivery of B2 Agonists in Intubated Patients, Nitric Oxide, Oxygen, Prostacyclin, Sildenafil
Cardiovascular: Adenosine, Adrenaline (Epinephrine), Amiodarone, Classification of Vasoactive drugs, Clevidipine, Digoxin, Dobutamine, Dopamine, Levosimendan, Levosimendan vs Dobutamine, Milrinone, Noradrenaline, Phenylephrine, Sodium Nitroprusside (SNiP), Sotalol, Vasopressin
Neurological: Dexmedetomidine, Ketamine, Levetiracetam, Lignocaine, Lithium, Midazolam, Physostigmine, Propofol, Sodium Valproate, Sugammadex, Thiopentone
Endocrine: Desmopressin, Glucagon Therapy, Medications and Thyroid Function
Gastrointestinal: Octreotide, Omeprazole, Ranitidine, Sucralfate, Terlipressin
Genitourinary: Furosemide, Mannitol, Spironolactone
Haematological: Activated Protein C, Alteplase, Aprotinin, Aspirin, Clopidogrel, Dipyridamole, DOACs, Factor VIIa, Heparin, LMW Heparin, Protamine, Prothrombinex, Tenecteplase, Tirofiban, Tranexamic Acid (TXA), Warfarin
Antimicrobial: Antimicrobial Dosing and Kill Characteristics, Benzylpenicillin, Ceftriaxone, Ciprofloxacin, Co-trimoxazole / Bactrim, Fluconazole, Gentamicin, Imipenem, Linezolid, Meropenem, Piperacillin-Tazobactam, Rifampicin, Vancomycin
Analgesic: Alfentanil, Celecoxib, COX II Inhibitors, Ketamine, Lignocaine, Morphine, NSAIDs, Opioids, Paracetamol (Acetaminophen), Paracetamol in Critical Illness, Tramadol
Miscellaneous: Activated Charcoal, Adverse Drug Reactions, Alkali Therapies, Drug Absorption in Critical Illness, Drug Infusion Doses, Epidural Complications, Epidural vs Opioids in Rib Fractures, Magnesium, Methylene Blue, Pharmacology and Critical Illness, PK and Obesity, PK and ECMO, Sodium Bicarbonate Use, Statins in Critical Illness, Therapeutic Drug Monitoring, Weights in Pharmacology
Toxicology: Digibind, Flumazenil, Glucagon Therapy, Intralipid, N-Acetylcysteine, Naloxone, Propofol Infusion Syndrome
CCC Toxicology Series
General
Approach to acute poisoning, ECGs in Tox, Evidenced-based Tox, Toxicology literature summaries, Does anti-venom work?
Toxins / Overdose
Amphetamines, Barbituates, Benzylpiperazine, Beta Blockers, Calcium Channel Blocker, Carbamazepine, Carbon Monoxide, Ciguatera, Citrate, Clenbuterol, Cocaine, Corrosive ingestion, Cyanide, Digoxin, Ethanol, Ethylene Glycol, Iron, Isoniazid, Lithium, Local anaesthetic, Methanol, Monoamine oxidase inhibitor (MAOI), Mushrooms (non-hallucinogenic), Opioids, Organophosphate, Paracetamol, Paraquat, Plants, Polonium, Salicylate, Scombroid, Sodium channel blockers, Sodium valproate, Theophylline, Toxic alcohols, Tricyclic antidepressants (TCA)
Envenomation
Marine, Snakebite, Spider, Tick paralysis
Syndromes
Alcohol withdrawal, Anticholinergic syndrome, Cholinergic syndrome, Drug withdrawals in ICU, Hyperthermia associated toxidromes, Malignant hyperthermia (MH), Neuroleptic malignant syndrome (NMS), Opioid withdrawal, Propofol Infusion Syndrome (PrIS) Sedative toxidrome, Serotonin syndrome, Sympatholytic toxidrome, Sympathomimetic toxidrome
Decontamination
Activated Charcoal, Gastric lavage, GI Decontamination
Enhanced Elimination
Enhanced elimination, Hyperbaric therapy for CO
Antidotes
Antidote summary, Digibind, Glucagon, Flumazenil, HIET – High dose euglycaemic therapy, Intralipid, Methylene Blue, N-Acetylcysteine (NAC), Naloxone
Miscellaneous
Cocaine chest pain, Digoxin and stone heart theory, Hyperbaric oxygen, Hypoxaemia in tox, Liver failure in tox, Liver transplant for paracetamol, Methaemoglobinaemia, Urine drug screen
Critical Care
Compendium
Chris is an Intensivist and ECMO specialist at The Alfred ICU, where he is Deputy Director (Education). He is a Clinical Adjunct Associate Professor at Monash University, the Lead for the Clinician Educator Incubator programme, and a CICM First Part Examiner.
He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives. He was one of the founders of the FOAM movement (Free Open-Access Medical education) has been recognised for his contributions to education with awards from ANZICS, ANZAHPE, and ACEM.
His one great achievement is being the father of three amazing children.
On Bluesky, he is @precordialthump.bsky.social and on the site that Elon has screwed up, he is @precordialthump.
| INTENSIVE | RAGE | Resuscitology | SMACC
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Hi Chris,
I am pretty confident that Charcoal’s mechanism of action is by adsorption of Solids, Liquids & gases on its surface, and does not have any absorbing properties, and is very good due to its large surface area. Thats one of the reasons one of its use in daily life is as a good deodoriser for a refrigerator, and be reused by washing it again.