Fenfluramine in clinical practice: new therapy option for Dravet and Lennox–Gastaut syndromes

Fenfluramine is an antiseizure medication for the treatment of Dravet and Lennox–Gastaut syndromes. This review summarizes the literature on the efficacy and tolerability of fenfluramine and presents recommendations for practical therapeutic management. With regular monitoring, this medication is generally well tolerated and to date has shown no cardiac side effects such as valve insufficiency or pulmonary hypertension in the clinical development program. However, children may experience a loss of appetite and should be closely monitored for weight loss, and sedation was observed in several overweight patients due to rapid dosage titration; therefore, a slower dosage increase than recommended might be needed for children and adults. Drug interactions should be considered before and during therapy, and dosage reductions are necessary when the medication is used in combination with stiripentol. Furthermore, bromide levels could increase with this medication. Contact with the patient or their relatives is important to determine the general state of health, potential movement disturbances, and seizure frequency so as to allow for timely dosage adjustments during the titration phase.