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Prescription for Licorice Pills Was Almost Lethal

We love licorice. High-quality natural licorice candy is wonderful. But too much licorice, whether as candy or in pills, can be dangerous in not deadly.
Prescription for Licorice Pills Was Almost Lethal

When most people think of licorice (or liquorice in the UK), they imagine candy such as licorice twists, Panda All Natural Soft Licorice, Twizzlers, Good & Plenty or Dutch Licorice Cats. But licorice root (Glycyrrhiza glabra), from which natural licorice candy is derived, has been around for millenia.

Licorice has been used medicinally by herbalists for thousands of years. The ancient Greek physician Pedanius Dioscorides is reported to have prescribed licorice root for the army of Alexander the Great. The herb was supposed to give the troops stamina and help them retain fluid on long marches so that if water was scarce licorice would keep them going. It was also used to treat stomach upset and other common ailments.

There is a dark side to licorice, however, as this reader discovered unexpectedly.

Q. My naturopath prescribed licorice pills to ease nausea and acid reflux. A month later I was in the emergency department with high blood pressure, irregular heartbeats, chest pain and lightheadedness.

My potassium was too low, whereas a month earlier it was within normal limits. I searched licorice and potassium and found a link. I have thrown away the licorice pills and after a few days of potassium pills prescribed by the ER doctor, I am starting to feel normal.

Overdosing On Licorice:

A. Your naturopathic doctor was irresponsible to prescribe licorice pills without careful monitoring. Although natural licorice might help with stomach upset, its active ingredient, glycyrrhizin, can cause fluid retention, hypertension and low potassium. This could lead to irregular heart rhythms that could be life threatening.

Medicinal Uses for Licorice Pills:

Licorice has been used for a variety of common conditions. It was frequently an ingredient in old-time cough drops for its sweet flavor and soothing properties. Its anti-inflammatory activity is theoretically good for the throat, lungs and digestive tract. There is research going back decades suggesting that prescribed licorice pills could be helpful against stomach ulcers.

A randomized controlled study published in the Brazilian Journal of Infectious Diseases (online, Sept. 8, 2016) reported that when physicians added licorice to standard antibiotic treatment, it was possible to eliminate the bacterium Helicobacter pylori (H. pylori) more successfully. This germ is responsible for many cases of peptic ulcer disease around the world. It is frequently treated with amoxicillin and clarithromycin, but resistance to these antibiotics is becoming common. That’s why these Brazilian scientists were trying to boost effectiveness with licorice, which has both antibacterial and antiviral activity.

They concluded:

“Because of the unsatisfactory rate of H. pylori eradication by the standard triple regimen, especially in areas with high resistance rates to clarithromycin and amoxicillin, adding licorice to the triple regimen significantly increase H. pylori eradication in patients with PUD [peptic ulcer disease].”

The Deadly Dangers of Licorice Pills:

As already mentioned, natural licorice can be dangerous. In addition to causing fluid retention, hypertension, potassium loss and arrhythmias, licorice pills can affect hormone levels. Decades ago we stumbled across this case report from the Department of Endocrinology of the Karolinska Hospital in Stockholm, Sweden (Lancet, Feb. 10, 1979):

“A 22-year-old gymnastics teacher without any previous serious illness or medications was investigated in 1973 because of secondary amenorrhea [loss of periods] and impaired libido…

“In 1977, she attended [the] hospital because of attacks of severe headache for 11/2 years. During attacks, which occurred about once a month, the pain began in the forehead and then spread, ending in vomiting and photophobia [sensitivity to light]. Blood pressure during attacks and during observation period on the ward was 240-210/130-110…with pulse rate of 44-60/min.

“On careful questioning the patient said that she had for several years been eating excessive amounts of liquorice. When the liquorice was withdrawn, the blood pressure returned to normal within 2 weeks…after 6 months, when the hormone levels had gradually returned to normal, menstruation returned. She has had no headache attacks…The symptoms of this patient–headache, vomiting, and photophobia–indicate liquorice toxicity…”

The hormone that was affected by her overconsumption of licorice was prolactin. Her levels were elevated, leading to some of the complications she experienced. Needless to say, a blood pressure of 240/130 could have led to a stroke.

A Safer Licorice?

Is there a way to get the benefits of licorice without the dangerous complications? A safer alternative might be deglycyrrhizinated licorice (DGL). With the glycyrrhizin mostly removed, licorice is less likely to cause dangerous side effects. You can find DGL in many health food stores and some pharmacies. Not everyone can tolerate DGL, however. Here is a report from Tania in San Diego:

“I am on my second bottle of DGL. While it does help my heartburn, it gives me horrible headaches. About 10 minutes after I take it, my head begins to pound. I’m going to have to find another natural alternative for GERD.”

Linda in Ohio saw her blood pressure go up:

“I too have been taking DGL for my stomach and it does work. Before I started it my blood pressure was in good control. I had lost about 15 pounds and my doctor was very happy.

“I started to notice my blood pressure was going up over the 30 days I was taking DGL (I had been told by my doctor this would not happen). I have decided to stop it and see if it goes back down. Also I feel my heart beating in my chest which I never did before and I have no heart problems.”

These case reports suggest to us that some people may react to DGL even with most of the glycyrrhizin removed. Then again, the FDA does not monitor such products, so who knows which ones are truly deglycyrrhizinated? Bottom line: monitor your body very carefully when taking any form of licorice!

Don’t Overdose on Potassium:

We understand that the person who contacted us initially about the licorice pills ended up with very low levels of potassium. We would caution her not to take potassium pills indefinitely since too much of this mineral can be as dangerous as too little. A blood test is essential to determine when potassium levels are back to normal.

People who would like other natural approaches for controlling heartburn may find our Guide to Digestive Disorders of value.

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About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
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