Medicinal use of barberry goes as far back as ancient Egypt, where pharaohs and queens took it with fennel seed to ward off the plague. Today, it is said to ease the pain of arthritis and rheumatism, and the flare-ups of psoriasis. The types of infections that barberry can help fight involve the throat, urinary tract, gastrointestinal tract, and lungs, as well as yeast infections and diarrhea.

The bark of the root and stem are used for medicine. Both are yellow, and Native Americans and Europeans used them for dyeing cloth. But the ingredients in the bark are also what make barberry a useful medicine. The bark contains alkaloids that are considered antibiotic by some people, and which cause, according to herbalists, infection-fighting stimulation of your body's mucous membranes.

In order to understand what this means, if you place a drop of barberry on your tongue, you will probably feel your mouth water. This is not because it tastes good; it's actually somewhat bitter. But as your mouth waters, according to herbalists, it is helping the body to fight infections. It does this by stimulating parts of your body's immune system.

If you have been taking antibiotics frequently because you get the same infections over and over again, your health care provider may discuss herbal alternatives to prescription drugs. There are many reasons for this. Barberry may help you feel better and give you a break from other treatments. Also, resistance to antibiotics is rising. In order to avoid this, many providers are looking into other ways to treat illnesses. Another reason is that your body changes in response to antibiotics, and these changes are not always good. The normal bacteria that we all have inside us, which actually helps us to fight against infection, can get wiped out with regular antibiotics. Your provider may want to help you restore these "good" bacteria by letting you have a little time off from antibiotics.

Barberry may also be recommended to you as an ointment for arthritis or psoriasis for similar reasons: medicines used regularly to treat these conditions can upset your body's balance. Often, the side effects caused by strong medications trigger reactions in the body that can seem like an entirely new illness.

Whatever the reason, once you and your health care provider have decided that discontinuing medications will pose no risk to your health, barberry may be recommended. It may also be recommended as a preventive method.

Barberry is a shrub that can grow to about nine feet and has gray, thorny branches. Its leaves have spiny teeth. Between April and June, bright yellow flowers bloom. These become dark red berries in the fall, which grow in drooping bunches. You can use the ripe berries for jam, or in ways similar to cranberries. Barberries are a little more sour and less bitter than cranberries.

Barberry bark and root bark contain many types of chemicals called isoquinoline alkaloids. Scientists and researchers have studied these constituents for many years, and have found that they do indeed have antibiotic actions. Some of them lower fevers, reduce swelling, lower blood pressure, and help normalize heart rate and the contractions of the heart muscle.

Barberry comes as tea, powdered in capsules, in fluid extracts or tinctures, and as a topical ointment. Extracts are standardized to 8 to 12% isoquinoline alkaloid content.

You should never take barberry longer than five to seven days. If your stomach is sensitive, three to five days is probably long enough. For sore throats, bladder infections, diarrhea, bronchitis, or yeast infections, choose from the following.

• Tea: 2 to 4g steeped dried root three times daily
• Tincture (a 1:5 solution made from herb and alcohol, or herb, alcohol, and water): 3 to 6 ml (1/2 to 1 1/2 tsp three times daily)
• Dry extracts: 250 to 500 mg three times daily
• For arthritis/psoriasis/skin disorders: 10% extract of barberry in ointment, applied to the skin three times daily

It is important to remember that some infections can be very dangerous if regular antibiotics are not taken for them. Never try to take an herb like barberry in place of a stronger antibiotic if a stronger antibiotic is needed. Make sure to follow your health care provider's instructions.

Barberry is safe with appropriate use, but do not use it if you are pregnant.

No noteworthy interactions (positive or negative) between barberry and conventional medications are known to have been reported in the literature to date.

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