Reviewed: Carnevali I, La Paglia R, Pauletto L, et al. Efficacy and safety of the syrup “KalobaTUSS®” as a treatment for cough in children: A randomized, double blind, placebo-controlled clinical trial. BMC Pediatr. January 2021;21(1):29. doi: 10.1186/s12887-020-02490-2.

Cough can be one of the most bothersome symptoms of upper respiratory tract infections in children. Acute cough, defined as a cough lasting less than three weeks, can affect a child’s quality of life, disrupt sleep, and lead to missed school. Parents often treat their children with over-the-counter antitussive drugs, although these medications sometimes have limited efficacy. In some human clinical studies, honey has been shown to relieve cough. The cough syrup KalobaTUSS® (Schwabe Pharma Italia; Egna, Italy) was developed to treat acute cough in children. It includes honey and extracts of common mallow (Malva sylvestris, Malvaceae), elecampane (Inula helenium, Asteraceae), plantain (Plantago major, Plantaginaceae), and shrubby everlasting (Helichrysum stoechas, Asteraceae). The authors conducted a randomized, double-blind, placebo-controlled clinical trial to evaluate the efficacy and safety of KalobaTUSS in children with acute cough.

The study was conducted from February to May 2019. Patients were recruited from pediatric consulting rooms of the Azienda Ospedaliera Provinciale hospital in Messina, Sicily, Italy. Children aged 3-6 years who had acute cough for at least three consecutive days were eligible for the study. According to the authors, a pediatrician ruled out “asthma or other hyperactive airway diseases as the cause of the cough.” However, the authors did not mention specific diagnoses (e.g., cold, flu, bronchitis, pneumonia, etc.), if any, for the children included in the study.

Fifty-four eligible participants were randomly assigned to take KalobaTUSS syrup, and 52 were assigned to take placebo syrup containing 20% fructose and unspecified excipients. The two interventions were taken in four 5-mL doses daily for eight days. Primary outcomes were changes in nighttime and daytime coughing, measured at baseline and after one, four, and eight days of treatment. The secondary outcome was the safety of the treatment syrup, evaluated by any adverse effects. The clinical efficacy of KalobaTUSS was assessed by using a six-point Likert scale, on which the parents rated their child’s cough from 0 (no cough) to 5 (“disturbing” cough).

At baseline, the mean period of coughing was 3.52 ± 0.58 days for the placebo group and 3.53 ± 0.57 days for the treatment group. None of the children needed antibiotics or any other drugs during the study, according to the authors. The median age of the patients was 4.4 ± 1.0 years.

The nighttime coughing score decreased significantly in the treatment group compared to the placebo group at day 1 (P = 0.00001), day 4 (P = 0.00014), and day 8 (P = 0.00758). Compared with the placebo, KalobaTUSS significantly reduced daytime coughing after one day of treatment (P < 0.00001). The differences in improvements in daytime coughing continued to be greater in the treatment group compared with the placebo group on day 4 (P = 0.00804) and day 8 (P = 0.03940). Both nighttime coughing and daytime coughing had subsided in more patients in the treatment group than in the placebo group at days 4 and 8 (P < 0.01).

No adverse effects were reported during the study in either group. The results are limited by the collection of subjective data on cough severity from the children’s parents and lack of information on the children’s diagnoses. The authors concluded that KalobaTUSS is “well tolerated and exerts positive effects by reducing the severity and shortening the duration of cough in children.”