EPM and Herbs

There is much controversy surrounding why horses get Equine Protozoal Myelitis (EPM) - a protozoal invasion of the central nervous system. There is no good answer and no single theory. Theories range from protozoa in opossum droppings through dysfunctional immune systems to contaminants in medications and pharmaceuticals. There may be truth in all of these, and research keeps on searching for more information, but the logical choice of which to accept and address is the immune system dysfunction. We can't rid the world of opossums and protozoa any more than we can guarantee a contaminant-free environment. But we can support and protect the immune system in many ways. And by supporting and strengthening the immune system we can maximize protection against many, many other challenges.

Unanswered questions are found also in the attempts to diagnose EPM. Some of the tests currently being used to diagnose EPM are not conclusive; blood tests for antigens may show a symptomless horse as positive and a horse with severe symptoms as negative. An inconclusive or inaccurate diagnosis may lead to an unnecessary prescription of drugs that can be as devastating to the horse as his symptoms. Even with a correct positive diagnosis, the drugs, which are harsh and often cause side effects such as anemia, may not have the desired effects.

Once the symptoms are evident and particularly if they have been there a long time, in true EPM as well as in other nerve damaging conditions, there may have already been enough damage done that the symptoms are difficult to reverse to any degree. Still, we can look at some of the clinical symptoms presented by the horse, and treat him according to them. A definitive diagnosis is not always needed in the world of complementary therapies, which has a lot to offer where conventional medicine has little or nothing.

Chinese herbs

For EPM horses and horses with EPM-like symptoms, we now have very encouraging news regarding the use of herbs. Both western and Chinese herbs have brought about many very positive results. Rapid, dramatic turnarounds have been achieved in many cases, even in some that were considered hopeless.

In Albuquerque, New Mexico a pair of holistically minded individuals, Mona Boudreaux, DVM, and Gary Allen, LAc, are teaching the secrets of their herbal success to veterinarians around the country through a course on Chinese herbs and how to use them effectively. Though Dr. Allen, a horse owner and human acupuncturist, and Dr. Boudreaux, a small animal veterinarian who practices only complementary medicine, are not equine specialists, they do know their herbs and are experts in the field of Chinese medicine. That is what they emphasize - Chinese medicine - when they teach their course to small and large animal veterinarians.

Where did it all start regarding EPM? Dr. Boudreaux says, "I had been a teaching assistant for the IVAS acupuncture course for two years and then hosted the acupuncture course. I had also studied herbs because I knew I still had a lot of learning to do, and I realized that the veterinary community didn't have a lot to offer. There were no herbal courses out there, so I decided to develop one. It was also a way for veterinarians to get together and share their knowledge and experience," she says.

Dr. Allen adds, "Then a veterinarian attending one of the courses said she had an EPM horse and asked how we would look at EPM from a Chinese medical standpoint. Consequently, Dr. Boudreaux and I put together a Chinese herbal formula that the veterinarian started using on the horse and there were some pretty drastic and dramatic positive changes in the horse. Other veterinarians then heard about it and tried it and it sort of snowballed from that point." Dr. Boudreaux and Dr. Allen then devised a 'basic formula' of Chinese herbs that can be used as the basis for a tailored-to-the-individual formula, and they are finding that horses of all kinds are responding well to it.

"I have horses of my own," says Dr. Allen, "and actually that's how we got the equine veterinarians involved. I had our regular veterinarian come out to look at our mare's bladder infection; I just wanted to make sure everything was ok. He suggested a shot of antibiotics and a steroid and I asked, 'Well how about if we try using herbs first?' Our veterinarian said, 'It's your horse, you can do whatever you want; I'll call back in three days'. Three days later he came out and looked at her and the infection was gone. Eventually he came and took the course, and is using herbs now with his patients.

"Then this same veterinarian was on his way to euthanize an EPM horse and thought about the work we were doing with herbs and EPM. He suggested the owner try a week of the herbs and see if it would make a difference. This mare was a show mare, and with the herbs got back to a point where she could show again. This doesn't mean that every patient is going to be that way, but we have found that a very high percentage of the patients have responded positively."

Says Dr. Boudreaux, "According to Chinese medicine, when the body is in balance, it cannot have disease. For example, just because you're exposed to a cold, whether it's viral or bacterial or whatever, does not mean you're going to get it." If the body is not in balance, however, the immune system can be compromised and one can become vulnerable to disease. By using the principles of Chinese medicine one can work with the immune system to try to reestablish immune system function.

Dr. Allen explains, "From a Chinese medical standpoint, what we are looking at with EPM is a an immune system dysfunction. That's one of the big things that both eastern and western medicine will concur on. Most veterinarians who have been working with it for a long time agree that we're looking at an autoimmune disorder as much as the protozoa that get into the spinal column and so on. We'll also see what we call a spleen chi [energy] deficiency, and at the same time you're going to see a kidney essence and liver deficiency. So Chinese medicine looks at it from that standpoint. The reason it is looked at that way is that the spinal column in Chinese medicine is looked at as an extra part of kidney essence. When we do the diagnostics according to Chinese medicine we find severe deficiency in these areas in a lot of horses. When we start treating and tonifying those individual areas and supporting the immune system, the horses begin to improve drastically. As they improve, we watch the clinical symptoms and adjust the formulation accordingly to get the horses back to responding and acting as they were before the onset of the symptoms of the disease. So far we have been very successful in what we've been doing with it."

He continues, "It is sometimes difficult to correlate directly across from a Chinese medical standpoint to how we look at it from a western standpoint. You'll see some similarities; you'll also see some differences. It's almost imperative that you have someone who's been trained in how we diagnose disorders to be able to use these herbs and use them efficiently. This is a whole new field for most veterinarians; they're just getting into the herbal aspect. They've been doing acupuncture on animals for a number of years in this country, but it has just been in the last three or four years that they've really been taking a look at the herbal aspect."

Diagnosis is achieved not by drawing blood or fluid from the body, but by using the diagnostic method according to the way Chinese medicine looks at disease. Once the diagnosis is determined, the treatment protocol can be devised, and this is how the herbs are carefully selected and combined.

Dr. Allen explains, "Performing diagnostics can include everything from palpating the patient to taking all the clinical signs and symptoms, and taking pulses, of which there are 27 different types in Chinese medicine that help us to diagnose and locate where the disease disorder is located in a body. We look at the tongue, the overall family history of the patient, the constitution of the patient, and we look at how the disorder or the disease is attacking the patient. So all these things come together into a time-proven diagnostic method to come up with how we would describe an illness or disorder. If the horses have had western clinical tests done, it may help to point us in a certain direction but it's not necessarily imperative."

Of the many horses that responded to the herb therapy, some had conventional therapy as well and some did not. "Because I do only alternative, or complementary, medicine in my practice many of the cases I get are one foot in the grave," says Dr. Boudreaux. When we first started working with this, a lot of the horses we got were horses that had already done the western medicine and it had not worked. Now we are getting more and more veterinarians educated on the use of Chinese herbs and they are either using it in conjunction with the conventional medicines or they're at least starting it a little bit earlier than one foot in the grave. They call us and say 'I've got an EPM horse and it's got these symptoms and the pulse is this, and the tongue looks like this', and we make up a formula, or we may send them just the base formula for EPM, and they may or may not modify it.

"There could be 10 EPM horses with many of the same major symptoms yet each may have slightly different symptoms," says Dr. Boudreaux, "so we put together a basic, and I hate to say it, but 'cookbook' formula, that would cover the majority of the most common signs. But the way to really use it is to start with it as your base formula and then modify it to each specific animal. Just like there are different herbal products on the market for skin rash and things like that which will suit the majority of the cases, that's basically the way it is with the EPM formula. But the true art of Chinese medicine is to individualize each formula you use with each patient, because each patient can be different even with the same western diagnosis."

Dr. Allen adds, "Every individual patient is going to have something that will be different from a previous patient, so you make adjustments with the herbs for that particular patient as needed. Most of the horses are under treatment with the herbs about 90 - 120 days. Most of them are responding very favorably within 30 days. Actually a number of them are responding to where you can see visible effects and differences in the patient within 10 days. Usually symptoms have dissipated by about 80 percent in 30 days. Whether we need to continue for a full 90-100 days, I really don't know yet. A number of veterinarians around the country who are utilizing it and keeping track of what they're doing have come up with the 90-100 days because that's what they are used to doing with the other medications."

Dr. Boudreaux says, "One of the things we don't have enough stats on is what's the best complete protocol to work with regarding exercise, diet and other modalities. I'm working with an equine veterinarian who sees a lot of EPM so that we can get more data on how to properly combine or incorporate acupuncture, herbal, and western medicine, so hopefully in the next year we'll have a lot more information on how to work with these cases better.

And the ones that are not responding? Dr. Allen explains, "What we're finding is that there may be involvement of more severe constitutional disorders and deeper conditions in the body, or additional problems in conjunction with the EPM problems. As those are addressed, and as the veterinarians become more knowledgeable in being able to use this type of medicine, I think that we'll see even these cases show marked improvement."

Dr. Boudreaux adds, "Saving your horse from euthanasia is worth investigating alternative means."

For most of the patients, exercise was involved in the rehabilitation program when appropriate, and in some cases was imperative. Says Dr. Boudreaux, "At the beginning of rehabilitation exercise may not be advised, but once the horses start to regain their coordination exercise can be very beneficial; you've just got to be careful because of the neurological signs. I leave that up to the equine practitioners because they are more knowledgeable about working with the horses, and I just help them with the herbs." 

Dr. Allen adds, "For rehabilitation, you've also got to look at nutrition; it's not just a matter of putting some herbs in for the magic cure. You've got to look at the overall quality and type of food that they're getting, their environment, as well as how much exercise they are getting; all of these things need to be taken into consideration."

Western herbs

Moose, owned by Patti Duffy-Salmon, received herbal therapy to help him through EPM.

When looking at EPM support using western herbs, we see a similar approach: boost the immune system, and support the body as a whole. Individual symptoms will vary from horse to horse, and treatment should be planned and adjusted accordingly. There are many different properties and actions among herbs, and they vary in nutritional content. Some herbs are largely medicinal; some are largely nutritional. Some have increased action when combined with other herbs.

Patti Duffy-Salmon, equine herbal specialist from Shelbyville, Tennessee says, " Essentially, EPM causes signs of neurological dysfunction. The most common clinical manifestation of EPM is simple spinal ataxia [loss of coordination] and weakness. During the first three months of conventional treatment, the EPM horse will undergo severe stress to his body. Herbs can be used during this time for 'whole body support' while strengthening the immune system. A combination I like to use contains astragalus, Siberian ginseng, feverfew, nettle, yarrow, cleavers, dandelion leaf, calendula, and boneset." Patti's horse, Moose, is a rehabilitated EPM horse, and herbs played a major part in his turnaround. Moose and Patti have successfully performed in numerous events since his rehabilitation.

Other herbs and herbal combinations can be used specifically to treat related conditions, such as anemia, or to build the immune system, to detoxify and cleanse, and even to fight the protozoa that may be present. Pau D'arco tree bark is an excellent herb for the EPM horse as it has been found to have anti-protozoan properties, and it boosts the immune system as well.

Says Patti, "It is agreed that the positive EPM horse has a dysfunctional immune system; therefore a good course of action would be to put the EPM horse on immune-stimulating herbs. The immune system works by recognizing and destroying anything foreign to the body. This includes bacteria, microbes, foreign particles, toxic compounds, and even the protozoa. The herbs can build up the horse's strength and stamina to fight off the existing protozoa as well as increase his resistance to the protozoa, and hopefully prevent him from relapsing if exposed to high counts of protozoa in the near future. Cells in the circulatory and lymphatic systems are largely responsible for fighting off the invading organisms," she says.

"Herbs that boost the immune system," continues Patti, "are generally known as immunostimulants or adaptogens. These will help increase the activity of the immune system, but they are not specific to any disease. Adaptogens increase the body's resistance to stress and exert a balancing effect on the various systems of the body independent of the type of pathological condition. An adaptogen is harmless and shouldn't influence normal bodily functions more than necessary. Adaptogens help the body deal more effectively with stress and they also serve to recharge exhausted adrenal glands. Garlic and the Chinese herbs astragalus and Siberian ginseng are excellent adaptogens."

Also of value to the EPM horse is an herbal cleansing. Patti explains, "Cleansing is a valuable part of the rehabilitation process, especially for the EPM horse, or any horse, that has been on heavy drug therapies, particularly sulfa drugs. A thorough but gentle cleanse will help flush toxins and waste material from the body. Many herbs have the qualities to aid in the cleansing of the body by assisting the removal of waste material from the body. Some, such as lymphatic alteratives, flush the lymphatic system. Other herbs help to purify the blood while helping to build blood, which is especially helpful for EPM horses that are anemic. Cleansing helps to bring about an improved state of well-being through elimination."

Herbs contain a wide variety of balanced nutrients and have numerous medicinal properties. Supplementing with herbs can help restore balance, prevent disease, and aid in recovery from illness. Herbs are not necessarily the most appropriate course of action for every condition, so it is important to consult your veterinarian and qualified herbal specialist for guidance before treating with herbs.

"I also believe that allowing the body time to heal is important," says Patti. "I am seeing more and more owners wanting their horses to be well and rideable in under 3 months and sometimes this is not at all possible. EPM is a long term and sometimes chronic disorder. Even after the horse appears to be fully recovered, stress will be an important factor that may affect his health for the rest of his life."

When dealing with a case of EPM, the traditional drugs have a list of side effects, so it would be wise to consult with your herbal specialist before proceeding with any drug therapy that could further harm the horse. Treating at an early stage vastly improves the prognosis; timely treatment and proper management of the case can arrest the progression of disease and possibly bring about a reversal.

Be sensible and aim for prevention of disease by maintaining sound, health-promoting farm management practices. Learn about all the natural alternatives and use them wisely. Good supportive care such as proper nutrition, avoidance of unnecessary drugs and chemicals, and the correct implementation of natural therapies can do much to encourage repair and aid rehabilitation as well as to prevent disease.


"For prevention of EPM, as with anything," says Dr. Boudreaux, "you need to keep the horses healthy and avoid things that affect the immune system or alter their health. You need to keep the body balanced. If they're having trouble with digestion, are working too hard, don't work hard enough, are eating the wrong foods, drinking poor water, or whatever - all of these things affect the balance. Meeting their needs is just basic common sense for prevention of any disease. Keeping the body healthy will prevent a lot of things, not just EPM."

Factors that can adversely affect health include:

Drugs, especially steroids

Surgical procedures and general anesthesia

Chemicals and preservatives

Vaccinations (consider titers)


Excessive workloads and intensive training programs

Stress and pain

Management changes or new ownership

Trailering, especially long journeys

Severe weather conditions, especially very hot or very cold weather

Is there a brighter future for EPM horses?

"The science, the art, and the medicine of complementary therapies is not new," says Dr. Boudreaux. "It's been around for a long time. Red blood cells were discovered in China over a thousand years before western medicine discovered them. Though Chinese herbal medicine has been around a long time, we [veterinarians] are all trained in western medicine, so we are not taught the old traditionals such as acupuncture, herbs, etc. Now the training's starting to come around and people are going into either both types or just into the alternative. But I think the best of both worlds is what we ultimately need. I think that in the future we'll learn how to combine all these modalities and we'll have a combination of therapies. For example, I don't really know homeopathy but I'm very comfortable combining chiropractic, acupuncture, nutrition, herbs and sometimes glandulars."

"The reality of it all is we're still thinking about disease from a western viewpoint," says Dr. Boudreaux. "Even though there are some 'cookbook' natural remedies - if you have a headache you could take willow or feverfew to get rid of the headache - we still need to look at what caused the headache, and that's where it's really more of a circular balance versus a linear like in western medicine. Our medicine is going to be changing; a lot of it is changing. But it is still our western mindset about disease that needs to change."


This article is for informational purposes only and is not intended to replace veterinary or other professional care. Always include your veterinarian and herbal specialist in the care of EPM horses.

Natural Horse Magazine thanks Dr. Gary Allen, Dr. Mona Boudreax, and Patti Duffy-Salmon for their assistance in preparing this article

Mona Boudreaux, DVM, CVA is an IVAS certified acupuncturist and an AVCA certified chiropractor. She has studied herbal medicine in China and in New Mexico with Dr. Gary Allen and Dr. Keshuang Zhao. Presently she is a House Delegate for IVAS and on the Board of Directors for AAVA. She has developed a Chinese herbal veterinary course which she teaches together with Dr. Gary Allen in New Mexico.

Gary Allen, LAc, DOM is a graduate of the International Institute of Chinese Medicine and has been practicing in Albuquerque, New Mexico for several years. A national board-certified acupuncturist, he specializes in herbal medicine under the guidance of Dr. Keshuang Zhao, one of China's top herbalists. Dr. Allen has been on staff at IICM teaching basic foundations in Chinese Medicine. He has also been a guest speaker for the International Veterinary Acupuncture Society. Most recently he has been developing and co-hosting an herbal program for veterinarians with Dr. Mona Boudreaux, a local veterinarian.

Patti Duffy-Salmon, owner and master herbalist of Meadowsweet Acre Herbs, specializes in custom blended herbs for horses, especially for the EPM horse, laminitis, Cushings and PMS mares. Free phone consultations. Paper catalog and on-line catalog available. Visit Patti and her horse Moose at www.meadowherbs.com

Dr. Mona Boudreaux

1925 Juan Tabo NE, Suite E

Albuquerque, NM 87112


Fax 505-332-4775


Dr. Gary Allen

1925 Juan Tabo NE, Suite E

Albuquerque, NM 87112


Fax 501-332-4775


Meadowsweet Acre Herbs

181 Wildcreek Road

Shelbyville, TN  37160

931-684-8838 (please call during working business hours 9-5 M-F)

Email: psalmon@cafes.net


For information on the Chinese herbal veterinary course contact Dr. Mona Boudreaux at the above address or fax. This course is offered only to licensed veterinarians.