| Licorice is obtained from Glycyrrhiza glabra, varieties | | | | due to the effects of hypokalemia and hypernatremia. |
| of which are indigenous to Europe and Asia. The | | | | Licorice may cause edema, myopathy, and muscle |
| medicinal parts include the unpeeled, dried roots and | | | | cramps. Vision loss has also been reported. Use of |
| runners, the peeled dried roots, and the rhizome with | | | | licorice with antiarrhythmics such as procainamide and |
| the roots. | | | | quinidine may cause hypokalemia and torsades de |
| Licorice contains 7% to 10% glycyrrhizin (glycyrrhizic | | | | pointes. Use with antihypertensives may render the |
| acid), natural sugars, glucose, mannose, sucrose, | | | | antihypertensive medication less effective. Use of |
| flavonoids, isoflavonoids, and sterols (betasitosterol and | | | | licorice with corticosteroids may have an additive |
| stigmasterol). Glycyrrhizin is a glycoside 50 times | | | | effect. Patients using licorice with digoxin are at risk for |
| sweeter than sugar. Licorice has been found to | | | | hypokalemia and digoxin toxicity. Use of diuretics with |
| stimulate the release of secretin, a potential mediator | | | | licorice may worsen hypokalemia. Smoking may |
| of antiulcer activity. Carbenoxolene, a semisynthetic | | | | reduce the metabolism of licorice and lead to potential |
| ester of glycyrrhetic acid, is an active ingredient for | | | | licorice toxicity. |
| treating stomach ulcers. | | | | Patients who are pregnant, breast-feeding, or |
| Licorice has shown anti-inflammatory and antiarthritic | | | | hypersensitive to licorice, or those with hypokalemia, |
| effects by inhibiting prostaglandin activity, which may | | | | arrhythmias, diabetes, glaucoma, or history of |
| make it useful in treating pain and inflammation from | | | | cerebrovascular accident or renal, hepatic, or cardiac |
| arthritis. The active ingredient, glycyrrhetinic acid, inhibits | | | | disease should avoid the use of licorice. |
| II-betahydroxydehydrogenase, an enzyme that | | | | Clinical considerations |
| prevents cortisol from acting as a mineralocorticoid. | | | | Monitor patient for signs of hypokalemia or |
| Inhibiting this enzyme allows increased mineralocorticoid | | | | hypernatremia. |
| activity, or aldosterone-like activity, leading to sodium | | | | Assess other medications patient is taking for possible |
| and water retention and potassium excretion. Many | | | | interactions. |
| reports have been made about severe toxicity caused | | | | Monitor patient's blood pressure closely. |
| by these effects. Licorice is available in products such | | | | Warn patient to notify his health care provider if he |
| as Herbal Nerve (Canada), Licorice Power, Lightning | | | | develops swelling, muscle cramps, tiredness, or |
| Cough Remedy, Phyto Power, and Wild Countryside | | | | weakness. |
| Licorice Root. | | | | Warn patient not to take herb for symptoms prior to |
| Reported uses | | | | speaking with his health care provider, as this may |
| Licorice is used to treat stomach ulcers and as an | | | | delay medical diagnosis. |
| expectorant. It's also used in sweets, soft drinks, | | | | Tell patient to remind prescriber and pharmacist of any |
| medicines, and chewing tobacco as a flavoring agent. | | | | herbal or dietary supplement that he's taking when |
| Administration | | | | obtaining a new prescription. |
| Capsules: 5 to 15 g a day of licorice root (200 to 600 | | | | Advise patient to consult his health care provider |
| mg glycyrrhizin) by mouth a day; daily intake greater | | | | before using an herbal aration because a treatment |
| than 50 g of the herb is considered toxic | | | | with proven efficacy may be available. |
| Tea (steep 1 teaspoon oflicorice extract in 8 oz boiling | | | | Safety Risk Warn patient not to take large doses of |
| water for 5 minutes): 1 cup of tea after each meal | | | | licorice or use it for longer than 4 weeks at a time, |
| Drops: 25 drops taken four times a day. | | | | because of the risk of toxicity. |
| Hazards | | | | Research summary |
| Licorice can cause a variety of adverse reactions, | | | | The concepts behind the use of licorice and the claims |
| including numbness, tingling paralysis, hypokalemia, and | | | | made regarding its effects haven't yet been validated |
| hypernatremia. There have been reports of | | | | scientifically. |
| hypertension, heart failure, and arrhythmias, most likely | | | | |