There are many ways to treat abscesses in equine hooves. With or without paring out an abscess, information on two of the most popular methods of drawing out an abscess are discussed below.

Ichthammol for Abscesses

Ichthammol is a sticky salve (a medicinal ointment for healing or relieving wounds and sores. anything that soothes, mollifies or relieves) that is a derivative of coal tar that promotes drainage. Ichthammol is sometimes called “black ointment” or “drawing salve.” Ichthammol is also known as ammonium bituminosulfonate or ammonium bituminosulphonate. The three main ingredients are ichthammol (a sulfurous coal tar), yellow soft paraffin and wool fat (fats that provide a layer of oil on the surface to prevent water evaporation). Ichthammol is listed as a mild antiseptic. How ichthammol works is not fully understood.

Human dermatologists say there is no evidence that ichthammol draws out abscesses or infections. One reason there is not much evidence on what ichthammol can do is that they are just a folk remedy, says Dr. Alan S. Boyd, a professor of dermatology at Vanderbilt University in Nashville.

“It seems that people have been taking their cues from veterinarians,” he says. “Products like ichthammol have long been a go-to preparation for the treatment of abscesses on the bottom of horses’ feet. The advice to clients with a footsore horse is almost always to slather on the ichthammol.”

Ichthammol, for example, traces back to the 19th century. While there has not been much written about it, there are historical accounts of sulfonated shale oil being used to aid in wound healing that goes back as far as the 1400s. Then in the late 1800s, a dermatologist wrote about the salve, recommending its use in the treatment of eczema. To date, there are no double-blind placebo-controlled trials to be found testing ichthammol’s efficacy.  

There are also no systematic studies on the use of schist oil extracts such as ammonium bituminosulfonate and sodium bituminosulfonate as used as an abscess drawing salve. Ichthammol has no known effect with other medicines and does not seem to have any significant side effects in humans or horses.

Epsom Salts for Abscesses

Epsom salts can be used by soaking or foot poulticing. Soaking is done by placing the hoof in warm water with diluted Epsom salts (with diluted povidone-iodine best) for about 10 to 20 minutes, once or twice daily. A better and more effective use of Epsom salts is to use them as a poultice. Epsom salt paste (magnesium sulfate) is usually bought in jars or tubes with other ingredients such as methyl salicylate and menthol. There are several methods to make your own Epsom salt paste with the most common way from Epsom salt and vegetable glycerin. Epsom salt looks similar to table salt but is a completely different compound. Epsom salt is made of both magnesium and sulfate, whereas table salt is sodium.

Epsom salt has reportedly been used for more than 400 years, ever since an English farmer discovered that the “bitter water” in his wells had remarkable healing properties on skin rashes and injuries.

Epsom salts work on drawing out abscesses by a process called osmosis. Osmosis is the transport of water-soluble material through a semipermeable membrane from a region of high concentration to a region of low concentration. Epsom salts work by the imbalance in water concentration. For example, an abscess is more concentrated in the hoof than in Epsom salt. When you soak or use an Epsom salt poultice, the abscessed material moves out of the hoof into the lower-concentration region in the salt.

There are also no scientific studies verifying the efficacy of using Epsom salts soaks to treat hoof abscesses. Epsom salts do not seem to have any significant side effects when used for soaking or poulticing of abscesses.

References

Boyd, Alan S. (July 2010). “Ichthammol revisited". International Journal of Dermatology. 49 (7): 757–60. doi:10.1111/j.1365-4632.2010.04551.x. PMID 20618493. S2CID 7367995.

Fisher S, Ziv M (July 2020). “Efficacy of topical ichthammol 10% for hidradenitis suppurativa: Case series and systematic review of its use in dermatology.” Dermatologic Therapy. 33 (4): e13868. doi:10.1111/dth.13868. PMID 32558051.

Gayko G, Cholcha W, Kietzmann M (October 2000). “Anti-inflammatory, antibacterial and antimycotic effects of dark sulfonated shale oil (ichthammol).” Berl. Munch. Tierarztl. Wochenschr. 113(10): 368–73. PMID 11084753.

“Veterinary MRL: Report on ICHTHYOL-substances” (PDF). European Medicines Agency. September 2004. Archived from the original (PDF) on 2006-07-18.

Warnecke J, Wendt A (February 1998). “Anti-inflammatory action of pale sulfonated shale oil (ICHTHYOL pale) in UVB erythema test.” Inflamm. Res. 47 (2): 75–8. doi:10.1007/s000110050282. PMID 9535545. S2CID 9014012.

Drug Bank. go.drugbank.com/drugs/DB11341

Epsom Salt Council. epsomsaltcouncil.org

Epsom Salt for Infection – Effective Remedies to Treat Stubborn Infections

12.7: Molecular Transport Phenomena – Diffusion, Osmosis, and Related Processes. Physics – Libretext. Last updated Sept. 9, 2020.  phys.libretexts.org/Bookshelves/College_Physics/Book%3A_College_Physics_(OpenStax)/12%3A_Fluid_Dynamics_and_Its_Biological_and_Medical_Applications/12.07%3A_Molecular_Transport_Phenomena-_Diffusion_Osmosis_and_Related_Processes

Ichthammol. Science Direct. sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceutical-science/ichthammol.

Epsom Salt for Infection – Effective Remedies to Treat Stubborn Infections. How To Cure. Updated on March 19, 2020. howtocure.com/epsom-salt-for-infection/