Chinese medicinal herbs for sore throat

Chinese herbal medicines are commonly used to treat sore throat in China and among Chinese people worldwide. Their efficacy in treating sore throat has not previously been systematically reviewed.

To assess the efficacy and safety of Chinese herbal medicines for patients with sore throat.

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 3, 2006) which contains the Acute Respiratory Infections Group's specialised register; MEDLINE (1966 to August 2006); EMBASE (1980 to August 2006); AMED (1985 to August 2006); the Chinese Biomedical Database (CBM) (1975 to August 2006), and China National Knowledge Infrastructure (CNKI) (1994 to August 2006).

We only included randomised controlled trials (RCTs) assessing Chinese herbal medicines for the treatment of sore throat with the outcomes of recovery, inefficacy, and adverse events.

One review author contacted the trial authors of claimed RCTs. Three review authors extracted and analysed the data.

Seven trials involving 1253 participants were included. All trials were identified as being of methodologically poor quality (C category). All of the Chinese herbal preparations in this review were inadequately characterised and were assessed in one trial only. It is highly likely that there was selection bias or detection bias, or both, in all of the included trials. Conflict of interest may have been another factor in producing a positive result in three studies as the prepared drugs were made in the trial author's hospital. We did not perform a meta-analysis and the results of the studies are reported separately. Three formulations were shown to be superior to the control in improving recovery: Ertong Qingyan Jiere Koufuye was more effective than Fufang Shuanghua Koufuye for acute pharyngitis (OR 1.54, 95% Cl 1.11 to 5.74); Yanhouling mixture was more effective than the gentamicin atomised inhalation for acute pharyngitis (OR 5.39, 95% CI 2.69 to 10.81) for acute pharyngitis; and Qinganlan Liyan Hanpian was more effective than Fufang Caoshanhu Hanpian for chronic pharyngitis (OR 2.25, 95% CI 1.08 to 4.67). Four four formulations were shown to be equal in efficacy to the control.

Based on the existing evidence included in this review, the efficacy of Chinese herbal medicine for treating sore throat is controversial and questionable. We cannot recommend any kind of Chinese medical herbal formulation as an effective remedy for sore throat, due to the lack of high quality clinical trials.