Licorice

Licorice is traditionally used for coughs and as a soothing remedy for the skin. People also take it for spasms and inflammation, for bronchitis, rheumatism, and arthritis. You can also take licorice as a laxative. Many health care providers prescribe licorice root products for peptic ulcer and chronic gastritis. Some providers recommend licorice root to treat primary adrenocortical insufficiency.

Plant Description

Spanish licorice (Glycyrrhiza glabra) grows wild in some parts of Europe and Asia. A perennial that grows 3 to 7 feet high, licorice has an extensive branching root system. The roots are straight pieces of wrinkled, fibrous wood, which are long and cylindrical and grow horizontally underground. Licorice roots are brown on the outside and yellow on the inside.

Glycyrrhizin, an active ingredient in licorice root, is 50 times sweeter than sugar. Glycyrrhizin contains a compound called glycyrrhizic acid mixed with potassium and calcium salts. Glycyrrhizin and glycyrrhizic acid are beneficial for peptic ulcers. Licorice must always be used with caution because glycyrrhizin and glycyrrhetic acid can harm the adrenal glands.

What's It Made Of?

Licorice products are made from the roots and underground stems of the plant. Glycyrrhizin and glycyrrhetic acid are the most important substances in licorice. The roots also contain coumarins, flavonoids, volatile oils, and plant sterols.

Available Forms

Licorice products are made from peeled and unpeeled dried root. There are powdered root and finely cut root preparations, dry extracts, and liquid extracts. Some licorice root extracts have had the harmful compounds removed. These extracts are known as deglycyrrhizinated licorice (DGL), and do not harm the adrenal glands. You may want to use DGL if you have gastric or duodenal ulcers.

How to Take It

Licorice root extracts kill staph and strep infections, and acts against viruses such as HIV, hepatitis A, and herpes. Licorice root destroys the yeast that causes Candida infections. Scientific studies show that DGL reduces inflammation and is as effective as some prescription drugs for gastric ulcers.

You can take licorice in the following forms.

• Dried root: 1 to 5 g as an infusion or decoction three times a day
• Licorice tincture: 2 to 5 ml three times a day
• DGL extract: 0.4 to 1.6 g three times a day for peptic ulcer
• DGL extract 4:1: in chewable tablet form 300 to 400 mg 20 minutes before meals for peptic ulcer

Precautions

You should be very careful if you're taking large amounts of licorice products or if you chew licorice-flavored tobacco or use other licorice-flavored products. If so, you're at risk for licorice poisoning.

If you take more than 20 g of licorice a day, you might have a bad reaction. Too much glycyrrhizin causes a condition called pseudoaldosteronism, which makes you overly sensitive to a hormone in the adrenal cortex. This condition can give you headaches and make you feel tired. It can also make you retain water. An overdose of glycyrrhizin can lead to harmful conditions such as high blood pressure and even heart attack. These symptoms can show up within one week if you're taking more than 100 g of glycyrrhizin every day.

People don't usually die from taking too much licorice or glycyrrhizin, but you can have side effects even if you're taking just an average amount of licorice. Some people get muscle pain, and others get numbness in their arms and legs. Too much licorice can also cause weight gain.

You can avoid these problems if you keep your dosages within the recommended guidelines. If you have any medical problems or concerns, check with your health care provider.

Don't use licorice if you've been told you have high blood pressure, or a kidney, heart, or liver condition. If you're pregnant, do not take licorice products. If you're nursing, don't take licorice. No matter how healthy you are, don't use any licorice product for longer than four to six weeks.

Possible Interactions

If you are taking diuretics (except potassium-sparing diuretics) or other medications used to regulate blood pressure, do not use licorice products.

Because licorice may dangerously increase the risk of toxicity associated with certain heart medications like digoxin, this herb should not be taken with these medications.

Licorice increases the effects of corticosteroid medications and should be avoided while taking these drugs.

If you have diabetes and are taking insulin to control your blood sugar levels, you should avoid using licorice, which may interact with insulin.

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