Mahonia aquifolium / Oregon grape

A constituent of Oregon Grape Root, berberine, is being studied because it contains a specific multidrug resistance pump inhibitor (MDR Inhibitor) named 5′-methoxyhydnocarpin (5′-MHC)3.Basically, what this means is that it works to decrease bacterial resistance to antibiotics. A simplified view of how MRSA works in the body is that it has a pump in its cell and when antibiotics enter that cell the pump immediately pumps out the antibiotics so it can have no effect on the MRSA cell.

5′-MHC, which is derived from berberine-containing plants like Oregon grape root, stops that pumping action so the antibiotics can have an effect on the MRSA cell.

Of course drug companies are racing to patent this as a pharmaceutical drug. Some herbalists are using Oregon grape root alongside antibiotics to increase their effectiveness against this deadly infection.

Stermitz et al, in Proceedings of the National Academy of Sciences 2000 97:4 also found the presence of 5′-methoxyhydnocarpin in the root. Although in itself it possesses no anti-microbial activity, it strongly potentiates the action of berberine by disabling the bacterial resistance mechanism against both synthetic and natural antimicrobials. The implication is immense for creating synergistic combinations to attack the new breed of antibiotic resistant organisms.

No matter how you slice it, Oregon grape root is a strong antimicrobial Oregon grape root has been used to address minor to severe infections for hundreds, if not thousands of years. It was highly regarded among eclectic physicians for use against syphilis.

Berberis aquifolium has won its reputation chiefly as a remedy for the syphilitic taint. The more chronic the conditions or results of the disease, the more it has been praised. Some claim that if given early it will abort the tertiary stage, but this of course depends in most cases upon the resisting powers of the body and the care the patient takes of himself.

Harvey Wickes Felter, M.D. (1922)

Today herbalists use Oregon grape root for all kinds of infections24.

  • eye infections

  • vaginal infections

  • wounds on the skin

  • mouth infections1

  • inflammatory bowel conditions

  • infectious diarrhea (e.g., giardia and other parasites)

  • infections in the upper digestive tract (h. pylori)

  • urinary tract infections

  • sore throats

The energetics of Oregon grape root

Seeing this long list of ways herbalists use Oregon grape root to fight infections could seemingly give it the title of an “herbal antibiotic”. However, I find this term to be too simplified and often misleading.

We have a variety of herbs that are anti-microbials, meaning that they have some effect on pathogens. However, each one works in different ways, for different infections, and are best suited to the individual, not the disease.

To understand the complexity of each herb we can study it energetically.

Oregon grape root is bitter, bitter, bitter. I often use it when teaching people about the Taste of Herbs since it really is an archetypal bitter. I often say it is disastrously bitter.

As a bitter it is a cooling, draining and detoxifying herb. (More on detoxifying in the next section about the liver).

Because Oregon grape root cools, drains and detoxifies, it will be most effective when matched to a person who has hot, moist and possibly stagnant conditions. (Although herbalists don’t agree on the humidity factor with Matt Wood and Michael Moore saying it is more specific to dryness.)

Heat in the body is characterized by redness, inflammation, yellow secretions (or a yellow coating of the tongue) and, of course, heat. Moistness in the body is just that: weepy or infections that seep pus or leak fluids, especially fluids that are yellow.

Understanding the energetics of Oregon grape root and the type of person and infection it is best suited to will result in getting consistent effective results.


You’ll often see Oregon grape root referred to as a “berberine-containing plant”. Berberine is a chemical constituent found in several different plants that has been studied extensively. If you like to geek out on constituent studies check out the PubMed database and you’ll find studies showing berberine can lower blood glucose levels, stop infections and modulate inflammation.

Studying plants by their chemical constituents gives new insights or at least a different perspective on plants that wasn’t available to us even 200 years ago. However, it is very limiting and overly simplifying to assume that all herbs that contain berberine are used in a similar manner.

So while plants like goldenseal (Hydrastis canadensis), Barberry (Berberis vulgaris), Goldthread (Coptis trifolia), and Amur cork tree (Phellodendron amurense) all contain berberine, they aren’t necessarily used in the exact same manner. The differentiation between these plants is beyond the scope of what I can cover here.

Today [Oregon grape root] is one of the indispensable articles of herbal materia medica. It was first used as a bitter tonic to promote internal and external secretion in dry and atrophic diseases. Today it is sometimes used (or abused, really) as a “natural antibiotic” because the presence of germ-killing-berberine. This is a materialistic way of viewing a plant by its “active ingredient” rather than by the overall influence of its numerous constituents working together.

Matthew Wood

Earthwise Herbal: New World Medicinal Plants

Oregon grape root for the liver

Another area that Oregon grape root shines is as an hepatic, or as an herb for the liver.

In western herbalism most bitter herbs are considered to have some effect on the liver and the gallbladder. The bitter taste on the tongue stimulates saliva, which then creates a whole cascade of digestive functions and digestive enzymatic secretions.

Part of the bitter taste reflex is to promote the secretion of bile from the liver and the gallbladder, which helps with digestion, mainly in digesting fats.

Liver congestion is one of the main underlying causes of many issues I see in my clinical practice. Of course each herbal formula I give is specifically formulated for the person and the issues they are having. However, I often use a base combination of dandelion root and Oregon grape root for a wide range of liver issues. In this section we’ll look at a variety of health complaints that could potentially be solved by releasing a stagnant liver.

Seeing a list of liver congestion symptoms could easily lead one to believe that it’s a “fad” diagnosis that is vague and broad. The thing is, the liver performs many functions in the body and, therefore, correcting liver dysfunction can correct a wide range of problems! In Chinese medicine the Liver is considered to be the General of the body because it directs so many physiological functions.

The liver and the female reproductive system

Because the liver filters hormones, a congested liver can be the root cause of many menstrual problems, including irregular menstruation, flooding, cramping, bloating, headaches and PMS. It can also be the underlying cause of more severe dysfunctions in the female reproductive system, such as endometriosis, ovarian cysts and fibroids. Hepatic herbs like Oregon grape root can be combined with lymphatic herbs and blood moving herbs (and lifestyle changes) to address a variety of these complaints.

The liver and the skin

The liver is a main organ of elimination; when it is not functioning optimally other systems of elimination may be overwhelmed. We can clearly see this with the connection of the liver and the skin. Oftentimes a congested liver can play part of the role in things like skin rashes, eczema and psoriasis. Alterative herbs like Oregon grape root and dandelion are often used for people with these types of skin afflictions.

In moist eczema it has acted most satisfactorily, but has usually been given in conjunction with other treatment. Dr. Soper, in 1884, reported in the Therapeutic Gazette a most intractable case of moist eczema of an acute character covering the entire body. No other alterative was given. The case was cured in four weeks.


The liver and constipation or sluggish digestion

When the liver isn’t functioning optimally, digestion takes a hard hit! Inability to digest fats, bloating, gas, hemorrhoids and constipation can all be attributed to liver problems. I often add small amounts of Oregon grape root as part of my bitters blends to help move the liver in the case of sluggish digestion.

The liver and the eyes and head

In Traditional Chinese Medicine the liver is associated with the eyes. Dry eyes, red, eyes, excessively tearing eyes, macular degeneration, etc can all have a base in liver function. Also, some types of headaches are caused by poor liver function.

The liver and the musculoskeletal system and energy levels

If the liver isn’t able to filter the blood and remove toxins and metabolic wastes it can result in feeling aches and pains all over. It can also poorly effect energy levels; the liver is especially indicated when a person feels groggy upon waking.

I realize this is a lot of physiology in a monograph, but rather than simply listing all the “diseases” that Oregon grape root is good for, I wanted to give a more thorough explanation of how it all ties together. It’s also important to realize that it is often formulated with other herbs and lifestyle suggestions and is rarely a stand alone treatment. (Although I probably have to qualify that, as some herbalists only practice with simples.)

Energetically we still look for the same indications that we discussed in the section on infection. Heat and excess dampness are great indications. Does the person have a red tongue with a yellow coating? That’s heat. Is their pulse fast and wiry? That’s heat. Do they have eczema that is hot to the touch and weepy? That’s heat.

If someone doesn’t have heat symptoms Oregon grape root could still be used if it were deemed appropriate through other indications. However, more attention would be paid to the formula to ensure that it was a good match for the person.


Currently, western herbalists most often use the roots as herbal medicine, but the leaves and berries have historical and modern uses as well.

Since I have no experience with using the leaves medicinally I’ll rely on Robert Dale Rogers’ historical accounts.

The leaf tea was used for kidney, and stomach ailments, as well as rheumatism and lack of appetite. …the dried leaf is an excellent anti-microbial styptic for herpes and psoratic skin lesions. They contain alkaloids that act on cardiac and smooth muscle as an anti-spasmodic.

Robert Dale Rogers

The young leaves can be eaten. And when I say young I mean it! The older leaves become very tough and quite spiky. The young tender leaves have a slightly sour taste reminiscent of a citrus fruit.

Plant Preparations

We typically use the root or, if it is really woody, the root bark in herbal medicine.

When working with Oregon grape root make sure that your root or root bark is vibrant yellow! If it is no more than a cream color you really don’t have potent medicine. Unfortunately it can be hard to find really yellow roots in commerce, so I recommend harvesting your own (ethically!) or buying the tincture.

I also mostly use Oregon grape as a tincture, mainly because it is so incredibly bitter it can be hard for people to take as a tea.

It does work as a tea. The tea also works great as an external wash.

Oregon grape root can be used as a dye.

It can also be infused into an oil and made into a salve. Darcey Williamson recommends it combined with willow bark for aches and pains.