Licorice Root Extract vs DGL: Uses, Mulethi and Blood Pressure Risks

Skip whole licorice (powder, tea, tincture or glycerite) if you have high blood pressure, heart or kidney disease, low potassium, or are pregnant, and check with your doctor first if you take diuretics, digoxin, blood pressure medicine or corticosteroids.

What is licorice root extract?

Licorice is a perennial plant grown across Europe, the Middle East and Asia. The sweet, fibrous root is the part people use. NCCIH lists three species sold as licorice: Glycyrrhiza glabra, G. uralensis and G. inflata. In Chinese medicine the root is called gan cao. In Hindi it is mulethi, and in Ayurvedic writing it appears as yashtimadhu.

A licorice root extract is any preparation that pulls the root's compounds into a liquid or concentrated powder. That covers tinctures, glycerites, capsules and the extracts that flavor candy and tobacco. The word "extract" alone does not tell you whether glycyrrhizin is still in the product. That one detail matters more than anything else on the label.

Assyrian, Egyptian, Greek, Chinese and Indian healers all used licorice for coughs, asthma and wounds (NCCIH). Still, NCCIH concludes there is not yet enough high-quality evidence to back licorice for any specific health condition.

Why licorice can raise blood pressure

The main sweet compound in licorice root is glycyrrhizin (also called glycyrrhizic acid). In the body, it blocks an enzyme in the kidney, 11-beta-hydroxysteroid dehydrogenase type 2. That enzyme normally switches cortisol off before it can act like the salt-retaining hormone aldosterone. With the enzyme blocked, cortisol does that job instead. The kidneys hold on to sodium and water and push out potassium (MSKCC). Doctors call the result pseudohyperaldosteronism: it looks like an aldosterone excess, but aldosterone itself is actually low.

The effect shows up at ordinary intakes, not only in extreme cases:

• A 2017 meta-analysis pooled 18 studies (337 people) in which participants took at least 100 mg of glycyrrhizic acid a day. Systolic pressure rose by about 5.5 mm Hg on average, diastolic by about 3 mm Hg, and blood potassium fell (Penninkilampi et al., Journal of Human Hypertension, 2017).
• A 2024 Swedish crossover trial gave 28 healthy young adults licorice supplying 100 mg of glycyrrhizic acid a day for two weeks. Home systolic pressure went up by roughly 3 mm Hg, and renin and aldosterone dropped sharply. The authors note the World Health Organization had suggested 100 mg a day was unlikely to cause harm, and they argue that limit may need another look (af Geijerstam et al., American Journal of Clinical Nutrition, 2024).
• The European Scientific Committee on Food has advised staying under 100 mg of glycyrrhizin a day, which a review puts at roughly 60 to 70 g of licorice (Deutch et al., Foods, 2019).

When potassium falls far enough, the heart rhythm can become unstable. NCCIH warns that glycyrrhizin has been linked to irregular heartbeat and cardiac arrest, mostly with large or long-term intake. It adds that even small amounts have caused severe problems in people who eat a lot of salt or already have high blood pressure, heart disease or kidney disease. The 2019 review advises people over 40 and anyone with a history of heart trouble to avoid eating licorice in excess. The effect lingers, too: hormone levels can stay suppressed for months after someone stops (Patel et al., Cureus, 2021).

DGL vs whole licorice vs licorice flavoring

Three very different things are sold as licorice.

NCCIH points out that many US "licorice" candies use anise oil and contain no licorice at all. Black licorice that lists licorice extract carries the same blood pressure cautions.

Does DGL work for heartburn and ulcers?

DGL is popular for heartburn, indigestion and stomach lining support. The research is thin and mixed. Older controlled trials of a DGL product called Caved-S found no advantage over placebo for duodenal ulcers (Feldman and Gilat, Gut, 1971, 47 patients) and no faster healing of gastric ulcers (Engqvist et al., Gut, 1973).

Newer trials have tested a flavonoid-rich licorice extract sold as GutGard, which keeps glycyrrhizin at 3% or less. In one placebo-controlled study, people with functional dyspepsia who took it twice daily for 30 days reported fewer symptoms (Raveendra et al., eCAM, 2012). A 2025 trial of 200 adults with reflux symptoms found faster relief of heartburn and regurgitation over 28 days compared with placebo (Raj et al., Complementary Medicine Research, 2025). Those results apply to that one extract, not every DGL product.

DGL is not a free pass, either. A 2021 case report described a patient who developed high blood pressure, low potassium and a fainting episode after years of heavy DGL use for stomach pain (Patel et al., Cureus, 2021). Keep to label directions, and see a doctor about heartburn that keeps coming back. If you want a gentler herb for an irritated stomach or throat, our guide to slippery elm covers another traditional soothing option.

Mulethi powder benefits and traditional uses

In Ayurveda, licorice is treated as a tonic, an expectorant and a demulcent, an herb that coats and soothes irritated tissue (MSKCC). Mulethi has a long history as a remedy for coughs, sore throats and an inflamed stomach (Kumar et al., Journal of Contemporary Dental Practice, 2020). A review of Ayurvedic practice lists licorice root as the largest ingredient in a classic throat formula, taken with honey, and as a common part of cough blends (Pandey et al., eCAM, 2013). Learn more about this system in our Ayurveda basics guide.

Some of this has modern support, mostly for licorice used in the mouth and throat rather than swallowed in large doses:

• Sore throat after surgery: a meta-analysis of 5 trials (609 adults) found that a licorice gargle or lozenge before intubation cut the chance of a sore throat afterward by more than half (Kuriyama and Maeda, Journal of Clinical Anesthesia, 2019).
• Canker sores: NCCIH reports that a licorice mouth rinse might shrink ulcers and ease pain.
• Mouth sores during cancer treatment: a small Indian trial of 75 patients found yashtimadhu powder with honey eased radiation-related mouth sores (Das et al., Ayu, 2011). This needs confirmation in larger studies.

Mulethi powder is whole licorice, so it still contains glycyrrhizin. A pinch in honey or warm water for a few days of throat trouble is very different from a daily spoonful for months.

Extract vs root powder vs tea vs glycerite

• Root powder: the whole dried root, ground. You control the amount and can stir it into honey, warm milk or tea. It carries the full glycyrrhizin load of the root.
• Tea: cut root simmered in water. Naturally sweet, its strength depends on how much root you use and how long it simmers.
• Tincture or glycerite: a liquid extract. Tinctures use alcohol, while glycerites use vegetable glycerin, which suits people avoiding alcohol and adds sweetness. Unless labeled DGL, both are whole licorice. Our herbal extracts guide explains how these liquids differ.
• DGL tablets and capsules: processed extracts with most glycyrrhizin removed, usually taken before meals for digestive comfort.

Who should avoid licorice root?

Based on NCCIH, MSKCC and the 2019 review, whole licorice is a poor fit for people who:

• have high blood pressure, heart failure, heart rhythm problems or kidney disease
• have low potassium, or lose potassium from diarrhea or heavy drinking
• take diuretics, digoxin or other cardiac glycosides, blood pressure medicines, warfarin, or corticosteroids
• are pregnant: NCCIH notes that heavy intake (around 250 g of licorice a week) has been linked to delivery before 38 weeks
• are breastfeeding, since little is known about safety

The concern is concentrated, repeated intake. Tell your healthcare provider about any licorice you take, including teas and lozenges, because glycyrrhizin from several sources adds up.

Find it at William's

We carry both sides of the licorice family, so you can pick the form that fits your goal:

• Nature's Way DGL Ultra, 90 vegan capsules: deglycyrrhizinated licorice for people who want licorice for stomach comfort without the glycyrrhizin load.
• Natural Factors DGL chewable tablets, 400 mg, 180 tablets: a chewable DGL sweetened with xylitol and stevia, taken before meals.
• Now organic licorice glycerite (alcohol-free), 2 oz: a whole-root liquid extract in glycerin, a handy form for throat-soothing use. It contains glycyrrhizin, so the cautions above apply.
• Starwest organic licorice root powder, sold by weight: the closest match to mulethi powder, for honey pastes, teas and Ayurvedic recipes. Its label warns against use in pregnancy and with high blood pressure, heart, liver or kidney problems, edema or low potassium.

For more on the cut root and teas, see our licorice root guide.

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