Flavonoid- and polyphenol-rich natural cough syrup from licorice, marshmallow, and anise extracts: An efficacy and tolerability study

Acute cough is the most common and annoying symptom, often lasting for a prolonged duration; therefore, treating cough is vital. A natural cough syrup (NCS) rich in polyphenols and flavonoids derived from licorice, marshmallow, and anise extracts was formulated, developed, and registered as an herbal supplement in Saudi Arabia. This study aimed to evaluate the efficacy and tolerability of this NCS as an anti-cough syrup in patients with acute cough. The study was designed as a prospective, open-label, uncontrolled, multicenter, pharmacy-based observational study conducted in Saudi Arabia. Each participant completed a validated questionnaire assessing bronchitis severity score (BSS), and coughing severity was assessed by visual analog score (VAS) at baseline, on Day 3, and at the end of treatment (EoT; 7 to 10 days of therapy). Five hundred ten patients were enrolled, and 460 (90%) completed and mailed the questionnaire. The BSS and VAS scores at baseline were 8.5 ± 4.5 and 51.2 ± 17.7 mm, respectively. After daily treatment with NCS, the BSS and VAS scores were significantly reduced by 39% (P <0.0001) for both on Day 3, and by 73% and 75%, respectively (P < 0.0001), at the EoT. Additionally, most participants (95%) were satisfied with the effectiveness of the NCS. The present study demonstrated the efficacy of the NCS formulated from licorice, marshmallow, and anise extracts in reducing coughing and cough-related symptoms in patients with acute cough in a shorter period than the self-resolving effects. The NCS was well tolerated.