Licorice poisoning

Licorice is an extract from the Glycyrrhiza glabra plant which contains glycyrrhizic acid, or GZA. GZA is made of one molecule of glycyrrhetic acid and two molecules of glucuronic acid. The extracts from the root of the plant can also be referred to as licorice, sweet root, and glycyrrhiza extract. G. glabra grows in subtropical climates in Europe, the Middle East, and Western Asia. When administered orally, the product of glycyrrhetic acid is found in human urine whereas GZA is not. This shows that glycyrrhetic acid is absorbed and metabolized in the intestines in humans. GZA is hydrolyzed to glycyrrhetic acid in the intestines by bacteria. For thousands of years G. glabra has been used for medicinal purposes including indigestion and stomach inflammation. Some other medicinal purposes are cough suppression, ulcer treatment, and use as a laxative. Also, salts of GZA can be used in many products as sweeteners and aromatizers. The major use of licorice goes towards the tobacco industry, at roughly 90% of usage. The rest is split evenly between food and pharmaceutics, at 5% of usage each (Federal Register, 1983). Licorice extract is often found in sweets and many candies, some drugs, and beverages like root beer. They can also be used in chewing gum, tobacco products like snuff, and toothpaste. An increase in intake of licorice can cause many toxic effects. Hyper mineralocorticosteroid syndrome can occur when the body retains sodium, loses potassium altering biochemical and hormonal activities. Some of these activities include lower aldosterone level, decline of the renin-angiotensin system and increased levels of the atrial natriuretic hormone in order to compensate the variations in homoeostasis. Some other symptoms of toxicity include electrolyte imbalance, oedema, increased blood pressure, weight gain, heart problems, and weakness. Individuals will experience certain symptoms based on the severity of toxicity. Some other complaints include fatigue, shortness of breath, renal failure, and paralysis.

Many adverse effects of licorice poisoning can be seen and most are attributed to the mineralocorticoid effects of GZA. Depending on the dose and intake of licorice, serious problems and even hospitalization can arise. People with previously existing heart or kidney problems may be more susceptible to GZA and licorice poisoning. It is important to monitor the amount of licorice consumed in order to prevent toxicity. It is difficult to determine a safe level, due to many varying factors from person to person. In the most sensitive individuals, daily intake of about 100 mg GZA can cause problems. This is equivalent to 50 g licorice sweets. However, in most people, they can consume up to 400 mg before experiencing symptoms, which would be about 200 g licorice sweets. A rule of thumb says a normal healthy person can consume 10 mg GZA a day.