A 10-year-old boy suffered seizures after over-indulging in licorice sweets and that has led to calls for manufacturers to put a warning on the labels of licorice. 

After suffering a 2 minute tonic-clonic seizure, a 10-year-old boy was admitted to hospital in Bologna, Italy.  Three more generalized seizures occurred over the next few hours and so Dr. Davide Tassinari and colleagues used cranial computed tomography (CT) and magnetic resonance imaging (MRI), to investigate the possibility of posterior reversible encephalopathy syndrome (PRES), but the major clinical conditions that lead to PRES were all ruled out.

During a medical examination a week later doctors noticed that the boy's teeth were black. They found that he had been eating at least 20 licorice sweets each day for the past four months. This resulted in the consumption of 2.88 mg/kg of glycyrrhizic acid (one of the active ingredients of licorice), well above the World Health Organization's recommended maximum of 2 mg/kg.



This excessive consumption had resulted in his development of hypertension (or high blood pressure), and in turn PRES. After the boy stopped eating the sweets, his anti-hypertensive treatment was gradually reduced and his blood pressure returned to normal.

The authors note that the risk is particularly high for children with a low body weight. They recommend that licorice sweet manufacturers should state a recommended daily amount as a safety measure.

Citation: Davide Tassinari MD, Rosalba Bergamaschi MD, Ilaria Corsini MD, Susanna Landini MD, Benedetta Romanin MD, Elisa Ballarini MD, Fabrizio De Ponti MD, Filomena Carfagnini MD, Francesco Toni MD, and Filippo Bernardi, 'Posterior reversible encephalopathy syndrome associated with licorice consumption: a case report in a 10-year-old boy' Pediatric Neurology  doi:10.1016/j.pediatrneurol.2014.12.001