Medical use of activated charcoal
By Josephine Afema, Dale A. Moore, and William M. Sischo
History
The adsorbent property of charcoal was first documented in 1791, and the use of charcoal in medicine as an antidote for poisoning started in the 1830s (Andersen, 1946).
Medical use and potential mechanism of action
Activated charcoal directly adsorbs drugs or toxic substances thereby interfering with absorption by the digestive tract. In addition, activated charcoal is thought to interfere with enterohepatic and/or gastro- enteral recirculation of drugs or toxins from systemic circulation into the gastrointestinal mucosa and contents by binding to conjugated drug/toxin or de-conjugated drug/toxin with subsequent elimination through the intestinal contents. Another hypothesis suggests presence of charcoal in the intestinal tract causes back-diffusion of absorbed drugs or toxins from systemic circulation into the intestinal lumen with subsequent elimination of charcoal-drug/toxin complex from the gastrointestinal tract (Derlet and Albertson 1986).
If used short-term, activated charcoal is safe for most adults. Side effects include constipation and, on occasion, intestinal blockage and dehydration (Watson et al., 1986). Because of its ability to adsorb drugs, oral medication efficacy will be affected (Gaudreault, 2005). Some activated charcoal products contain sorbitol, which can act as a laxative or result in severe diarrhea in people (Islam and Sakaguchi, 2006). A study of people given multiple doses of activated charcoal documented hypernatremia and hypermagnesemia (Dorrington et al. 2003) and effects on fluid-electrolyte balance have been noted (Allerton and Strom 1991).
Evidence, knowledge gap and future research
The use of activated charcoal as an antidote for poisoning or drug overdose in humans and animals is well documented (Neuvonen, 1982). However, current studies on the efficacy of activated charcoal in treating diarrhea in humans or animals are few and suffer from improper study design. An in-vitro study documented activated charcoal was effective at adsorbing verotoxin and entero-hemorrhagic E. coli 0157:H7 (Naka et al., 2001). However, an in-vivo study reported activated charcoal was ineffective at adsorbing E. coli O157:H7 and Salmonella Typhimurium from the gastrointestinal tract of sheep (Knutson et al., 2006).
Activated charcoal combined with bamboo vinegar has been found effective at reducing clinical signs and duration of diarrhea and number of oocytes excreted in calves experimentally infected and goat kids naturally infected with Cryptosporidium (Paraud et al. 2011; Watarai et al. 2008). Overall, evidence is insufficient to support the use of activated charcoal in treating calf diarrhea (Constable 2009).
A study of dairy farmers surveyed their use of antimicrobial alternatives in treating calf diarrhea, 18% of conventional dairy farms and 35% of organic farms reported use of activated charcoal. Furthermore, 35% of conventional farms and 55% of organic farms perceived activated charcoal was effective in treating calf diarrhea. Additional research is recommended to evaluate alternative therapies for calf diarrhea (Habing et al., 2016). Randomized blinded clinical trials are needed to test the efficacy of activated charcoal in treatment of calf diarrhea. However, in a recent review of acute diarrhea management in children, the authors indicated there was no reason to use activated charcoal in these cases (Guarion et al., 2012).
| Drug | Study type | Main findings and/or mechanism of action Reference | Reference |
|---|---|---|---|
| Carbo med. Merck and charcoal preparation X | In vitro | Activated charcoal was effective in adsorbing several common poisons in vitro. The adsorptive capacity of charcoal depends on the preparation. | Andersen, 1946 |
| Activated charcoal (AC) | In vitro | This study investigated the capacity of AC to adsorb verotoxin producing E. coli 0157:H7 and verotoxin. AC adsorbed and reduced E. coli 0157:H7 cells dependent on dose with complete adsorption at 10 mg of AC. AC adsorbed and inhibited action of verotoxin. Study also investigated effect of AC on normal intestinal microflora and while there was a dose dependent reduction in the number of cells, 10mg of AC did not cause a complete reduction in normal bacterial flora. Conclusion: AC could be effective at adsorbing verotoxin producing E. coli 0157:H7 and verotoxin. | Naka et al., 2001 |
| Activated charcoal | Randomized clinical trial in adults with nonspecific diarrhea | Tested the efficacy and tolerance of AC plus rehydration fluids in 100 adults with nonspecific diarrhea. Treated group had less clinical signs and short duration of diarrhea compared to control group. Conclusion: AC in combination with rehydration fluids was effective in treating nonspecific diarrhea in adult humans. | Dorn, 2004 |
| Activated charcoal | In vivo (sheep) | Study determined if AC would effectively adsorb E. coli O157:H7 and Salmonella Typhimurium from the gastrointestinal tract of sheep. AC was not effective at adsorbing these organisms from the rumen, caecum, or rectum. | Knutson et al., 2006 |
| Obionekk® containing activated charcoal and wood vinegar liquid | In vivo (neonatal goat kids) clinical study | Study determined the efficacy of Obionekk® in preventing Cryptosporidium sp. in goat kids (3-17 days old) that were naturally infected under field conditions. Obionekk® significantly reduced oocyte excretion and clinical signs of diarrhea in goat kids treated 3 times a day compared to controls. | Paraud et al., 2011 |
| Activated charcoal and metronidazole | In vitro | AC with metronidazole caused a significant (3 log) reduction in E. coli O157:H7 compared to AC alone. | Ilomuanya et al., 2011 |
Conclusions
Charcoal comes in many formulations and is primarily sold in veterinary medicine as an adsorbent for ingested toxins. Some formulations with polysorbate or sorbitol may actually cause diarrhea and repeated doses may result in severe hypernatremia and fluid/electrolyte imbalance. Repeated doses may result in constipation or GI obstruction and because it is such an effective toxin adsorbent can affect the absorption of enteral antibiotics or other drugs. However, there is no current indication for the use of activated charcoal formulations in veterinary medicine for neonatal calf diarrhea.
References
- Allerton JP, Strom JA. 1991. Hypernatremia due to repeated doses of charcoal-sorbitol. Am J of Kidney Diseases. 17(5):581-584.
- Andersen AH. 1946. Experimental studies on the pharmacology of activated charcoal; adsorption power of charcoal in aqueous solutions. Acta PharmacolToxicol. (Copenh) 2:69-78.
- Andersen AH. 1947. Experimental studies on the pharmacology of activated charcoal; the effect of pH on the adsorption by charcoal from aqueous solutions. Acta Pharmacol Toxicol. (Copenh) 3:119-218.
- Constable PD. 2009. Treatment of calf diarrhea: antimicrobial and ancillary treatments. Vet Clin North Am Food Anim Pract. 25:101-120.
- Derlet RW, Albertson TE. 1986. Activated charcoal–past, present and future. West J Med. 145:493-496.
- Dorn M. 2004. [Controlled clinical testing of an antidiarrheal]. MMW Fortschr Med. 146(Suppl 2):57-60.
- Dorrington CL, Johnson DW, Brant R. 2003. The frequency of complications associated with the use of multiple-dose activated charcoal. Ann Emerg Med. 41: 370-377
- Gaudreault P. 2005. Activated charcoal revisited. Clin Ped Emerg Med. 6(2):76-80.
- Guarino A, Dupont C, Gorelov AV, et al. 2012. The management of acute diarrhea in children in developed and developing areas: from evidence base to clinical practice. Expert Opinon on Pharmacotherapy. 12(1):17- 26.
- Habing G, Djordjevic C, Schuenemann GM, Lakritz J. 2016. Understanding antimicrobial stewardship: Disease severity treatment thresholds and antimicrobial alternatives among organic and conventional calf producers. Prev Vet Med. 130:77-85.
- Ilomuanya MO, Ifudu ND, Uboh C. 2011. The use of metronidazole and activated charcoal in the treatment of diarrhea caused by Escherichia coli 0157:H7 in an in vitro pharmacodynamic model. African J Pharmacy and Pharmacology. 5:1292-1296.
- Islam MS, Sakaguchi E. 2006. Sorbitol-based osmotic diarrhea: Possible causes and mechanism of prevention investigated in rats. World J Gastroenterol. 12(47):7635–7641.
- Knutson HJ, Carr MA, Branham LA, et al. 2006. Effects of activated charcoal on binding E. coli O157:H7 and Salmonella Typhimurium in sheep. Small Rum Res. 65:101-105.
- Naka K, Watarai S, Tana, et al. 2001. Adsorption effect of activated charcoal on enterohemorrhagic Escherichia coli. J Vet Med Sci. 63:281-285.
- Neuvonen PJ. 1982. Clinical pharmacokinetics of oral activated charcoal in acute intoxications. Clin. Pharmacokinet. 7:465-489.
- Paraud C, Pors I, Journal JP, et al. 2011. Control of cryptosporidiosis in neonatal goat kids: efficacy of a product containing activated charcoal and wood vinegar liquid (Obionekk(R)) in field conditions. Vet Parasitol. 180:354-357.
- Watarai S, Tana, Koiwa M. 2008. Feeding activated charcoal from bark containing wood vinegar liquid (nekka-rich) is effective as treatment for cryptosporidiosis in calves. J Dairy Sci. 91:1458-1463.
- Watson WA, Cremer KF, Chapman JA. 1986. Gastrointestinal obstruction associated with multiple-dose activated charcoal. J Emergency Med. 4(5):401-407.