I hope someone will weigh in on charcoal.
What I can give you is this from Plumb's Veterinary Drug Handbook 6th (2008) edition (I believe the latest edition is the 9th).
Uses/Indications
Activated charcoal is administered orally to adsorb certain drugs or toxins to prevent or reduce their systemic absorption.
Pharmacology/Actions
Activated charcoal has a large surface area and adsorbs many chemi- cals and drugs via ion-ion, hydrogen bonding, dipole and Van der Walle forces in the upper GI tract thereby preventing or reducing their absorption. Efficiency of adsorption increases with the mo- lecular size of the toxin and poorly water soluble organic substances are better adsorbed than small, polar, water-soluble organic com- pounds.
While activated charcoal also adsorbs various nutrients and en- zymes from the gut, when used for acute poisonings, no clinical significance usually results. Activated charcoal reportedly is not ef- fective in adsorbing cyanide, but this has been disputed in a recent study. It is not very effective in adsorbing alcohols, ferrous sulfate, lithium, caustic alkalies, nitrates, sodium chloride/chlorate, petro- leum distillates or mineral acids.
Pharmacokinetics
Activated charcoal is not absorbed nor metabolized in the gut.
Contraindications/Precautions/Warnings
Charcoal should not be used for mineral acids or caustic alkalies as it is ineffective. Although not contraindicated for ethanol, metha- nol, or iron salts, activated charcoal is ineffective in adsorbing these products and may obscure GI lesions during endoscopy.
Adverse Effects
Very rapid GI administration of charcoal can induce emesis. If aspi- ration occurs after activated charcoal is administered, pneumonitis/ aspiration pneumonia may result. Charcoal can cause either con- stipation or diarrhea and feces will be black. Products containing sorbitol may cause loose stools and vomiting.
There have been reports of hypernatremia occurring in small dogs and cats after charcoal (with or without sorbitol) administration, presumably due an osmotic effect pulling water into the GI tract. Reduced sodium fluids (e.g., D5W, H normal saline/D2.5W) with warm water enemas can be administered to alleviate the condition.
Charcoal powder is very staining and the dry powder tends to “float” covering wide areas.
Overdosage/Acute Toxicity
Potentially could cause electrolyte abnormalities; see Adverse Effects for more information.
Prescriber Highlights
Orally administered adsorbent for GI tract toxins/drug overdoses
Not effective for mineral acids/alkalis
Too rapid administration may induce emesis/aspiration
In small dogs & cats, monitor for hypernatremia
Handle with care as charcoal stains clothing very easily; dry powder “floats”
Drug Interactions
The following drug interactions have either been reported or are theoretical in humans or animals receiving charcoal and may be of significance in veterinary patients:
OTHER ORAlly ADmINISTERED THERAPEUTIC AgENTS: Separate by at least 3 hours the administration of any other orally administered
therapeutic agents from the charcoal dose
DAIRy PRODUCTS: May reduce the adsorptive capacity of activated charcoal
mINERAl OIl: May reduce the adsorptive capacity of activated charcoal
POlyETHylENE glyCOl; ElECTROlyTE SOlUTIONS (e.g., Go-Lytely®):
May reduce the adsorptive capacity of activated charcoal
Doses
DOgS & CATS:As a gastrointestinal absorbent:
a) 10mLofa20%slurry(1gofcharcoalin5mLofwater)per kg of body weight by stomach tube (Carson and Osweiler 2003)
For acute poisoning:
- a) After decontamination of the GI tract give activated charcoal at 1 – 4 g/kg PO. Placement of a nasogastric tube can facili- tate administration and reduce the incidence of aspiration in the sedated/fractious animal particularly when repeated administration is desired; repeat every 4 – 6 hours for toxins that are recirculated through the intestinal capillary network. (Rudloff 2006b)
- b) 1–4g/kgin50–200mLofwater.Concurrentwithorwithin 30 minutes of giving charcoal, give an osmotic cathartic. Re- peated doses of activated charcoal may also bind drugs that are enterohepatically recycled. (Beasley and Dorman 1990)
- c) Administer in a bathtub or other easily cleanable area. Give activated charcoal at 1–5 g/kg PO (via stomach tube using either a funnel or large syringe) diluted in water at a con- centration of 1 g charcoal/5 –10 mL of water. Follow in 30 minutes with sodium sulfate oral cathartic. (Bailey 1989)
RUmINANTS:a) 1–3 grams/kg PO (1 gram of charcoal in 3–5 mL of water) via stomach tube; give saline cathartic concurrently. May repeat in 8 – 12 hours. (Bailey 1986b)
HORSES: a) Foals: 250 grams (minimum). Adult horses: up to 750 grams. Make a slurry by mixing with up to 4 L (depending on ani- mal’s size) of warm water and administer via stomach tube. Leave in stomach for 20 – 30 minutes and then give a laxative to hasten removal of toxicants. (Oehme 1987b)
monitoring
Monitoring for efficacy of charcoal is usually dependent upon the toxin/drug that it is being used for and could include the drug/ toxin’s serum level, clinical signs, etc.
Serum sodium, particularly if patient develops neurologic signs associated with hypernatremia (tremors, ataxia, seizures)
Client Information
This agent should generally be used with professional supervi- sion; if used on an outpatient basis patients must be observed for at least 4 hours after administration for signs associated with too much sodium in the blood (weakness, unsteadiness, tremors, convulsions). Should these occur, patients must immediately be seen by a veterinarian.
Charcoal can easily stain fabrics
Chemistry/Synonyms
Activated charcoal occurs as a fine, black, odorless, tasteless powder that is insoluble in water or alcohol. Commercially available acti- vated charcoal products may differ in their adsorptive properties, but one gram must adsorb 100 mg of strychnine sulfate in 50 mL of water to meet USP standards.
Activated charcoal may also be known as: active carbon, acti- vated carbon, carbo activatus, adsorbent charcoal, decolorizing car- bon, or medicinal charcoal. There are many trade names available.
Storage/Stability
Store activated charcoal in well-closed glass or metal containers or in the manufacturer’s supplied container.
Dosage Forms/Regulatory Status
VETERINARylAbElED PRODUCTS:
Activated charcoal 47.5%, Kaolin 10% granules (free flowing and wettable) in 1 lb bottles, and 5 kg pails: Toxiban® Granules (Vet-A- Mix); (OTC). Labeled for use in both large and small animals.
Activated charcoal 10.4%, Kaolin 6.25% suspension in 240 mL bot- tles: Toxiban® Suspension (Vet-A-Mix); (OTC). Labeled for use in both large and small animals.
Activated charcoal 10%, Kaolin 6.25%, sorbitol 10% suspension in 240 mL bottles: Toxiban® Suspension with Sorbitol Vet-A-Mix); (OTC). Labeled for use in small animals.
Activated Charcoal 10%, Attapulgite 20%, sodium chloride 35 mg/ mL, potassium chloride 35 mg/mL Gel/Paste in 80 mL & 300 mL: D-Tox-Besc® (AgriPharm); Activated Charcoal Gel with Electrolytes® & DVM Formula® (Bomac Plus Vet), Activated Charcoal Paste® (First Priority); (OTC). Labeled for use in small and large animals.
Activated Hardwood Charcoal and thermally activated attapulgite clay (concentrations not labeled) in an aqueous gel suspension in 8 fl oz bottle, 60 mL tube and 300 mL tube with easy dose syringe. UAA® (Universal Animal Antidote) Gel (Vedco); (OTC). Labeled for use in dogs, cats and grain overload in ruminants.
HUmANlAbElED PRODUCTS:
Activated Charcoal Powder: 15 g, 30 g, 40 g, 120 g, 240 g and UD 30 g (Activated charcoal is also available in bulk powder form); ge- neric; (OTC)
Activated Charcoal Liquid/Suspension with sorbitol: 15 g & 30 g in 150 mL & 50 g in 240 mL; CharcoAid®(Requa); 25 g in 120 mL & 50 g in 240 mL; Actidose® with Sorbitol (Paddock); (OTC)
Activated Charcoal Liquid/Suspension without sorbitol: 15 g & 50 g in 120 mL & 240 mL; CharcoAid® 2000 (Requa); (OTC); 208 mg/ mL—12.5gin60mL&25gin120mL;12.5gin60mL,15gin75 mL, 25 g in 120 mL, 30 g in 120 mL, 50 g in 240 mL; Actidose-Aqua® (Paddock); generic; (OTC)
Activated Charcoal Granules: 15 g in 120 mL; CharcoAid® 2000
