Deglycyrrhizinated licorice, or DGL, is a specific type of preparation derived from the licorice root. It is used differently than herbal licorice because it is much higher in agents that soothe or heal mucous membranes, and lower in other constituents found in licorice root and full extracts of licorice root. DGL may also be spelled, deglycyrrhizinated liquorice. The herb, licorice, from which DGL is derived, is known by the names Glycyrrhiza, sweet root, and Yasti-madhu with the glycyrrhizin removed.
Licorice is a perennial herb, which is native to the Middle East, and widely cultivated in Europe, the Middle East, and Asia. The root has a long history of use as a
Glycyrrhizin is the cause of pseudoaldosteronism, a condition mimicking the effects of excessive levels of the adrenal hormone aldosterone. The deglycyrrhizinated product was developed to concentrate the demulcent and healing aspects of licorice, while avoiding excess exposure to glycerrhizin and its adverse effects when taken in high doses.
Deglycyrrhizinated licorice is used to soothe and protect the lining of the stomach and duodenum (upper small intestine)—the common sites of gastric ulcers. Ulcers in the stomach are known as peptic ulcers, while those in the small intestine are duodenal ulcers. DGL has been studied for the treatment of peptic and duodenal ulcers, and appears to be both safe and effective for long-term maintenance therapy for certain patients who have these ulcers. Some marketers claim that DGL has anti-inflammatory, antimicrobial, and antioxidant activities. However these claims are unsubstantiated.
One study, using a mouthwash containing deglycyrrhizinated licorice, showed dramatic improvement in the healing and pain of mouth ulcers.
DGL is available as:
- capsules, 250 milligrams (mg)
- chewable tablets (with or without sugar), 140 and 380 mg
- lozenges, 400 mg
- wafers, 380 mg
- liquid, various concentrations
Deglycyrrhizinated licorice appears to be very safe. However, severe allergic reactions are possible. There has been one report of a case of nilk alkali syndrome in a patient who was drinking unusually large amounts of milk. This has led to a caution against taking calcium supplements and deglycyrrhizinated licorice at the same time. However, it is usually safe at normal dose levels.
Although there have been few studies conducted to determine whether interactions between deglycyrrhizinated licorice and conventional drugs exist, research has failed to identify problems.
Gastritis, nausea, and diarrhea are reported side effects.
All clinically significant adverse interactions with licorice have been due to the effects of the glycyrrizic acid. They would not be anticipated with this component removed. DGL reportedly reduces the gastric ulceration caused by aspirin and other nonsteroidal anti-inflammatory drugs.
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Samuel Uretsky, Pharm.D.