Acute upper respiratory tract infections (URTIs) are the most common diagnoses made in the primary medical services, which consisted of 34.6% of all diagnoses in Hong Kong. It accounts for approximately 100 million visits per year in the US. It was estimated that an adult has an average of 3 to 4 times while children has an average of 6 to 8 times each year. WHO has pointed out that URTIs have a great impact on personal and economical aspects although they are rarely lethal It was estimated that 60% of the working class has contracted URTIs each year, and a loss of 8.8 days of perfect health for each worker on average each year, and a loss of up to HK$ 31.3 billion of economic output each year.
There is no established curative treatment in Western medicine for URTIs except for selected cases of influenza. Studies have shown that the average duration of illness of an URTI is around 7 days, and most URTIs resolve by the 10th day. Traditional Chinese medicine (TCM) is commonly used by people in Hong Kong on its own or along side with Western medicine for the treatment of URTIs. The Chinese Medicine Council of Hong Kong was established in September 1999, the use of Chinese herbal medicine (CHM) is expected to increase and there is an urgent need for research evidence on their effectiveness and side effects. TCM follows a theoretical and methodological pathway, which leads to its diagnosis and treatment. Most URTIs can be differentiated into two types according to the theory of TCM: Wind-cold syndrome and Wind-heat syndrome. The theory leads to two classical herbal formulae that are very popular in Hong Kong: the Jing Fang Bai Du san for treating the Wind-cold syndrome whiles the Ying Qiao san for treating Wind-heat syndrome.
The Jing Fang Bai Du san can relieve external symptoms and effectively clear up the pathogenic cold. It contains 13 herbs including, Radix Angelicae Pubescentis, Radix Peucedani, Radix Ginseng, Smilacis Glabrae Rhizoma, Rhizoma Chuanxiong, Fructus Aurantii, Radix Platycodi, GlycyrrhizaeRadix, Herba Schizonepetae, Fructus Arctii, MenthaeFolium, Radix Saposhnikoviae, Rhizoma et Radix Notopterygii. Previous clinical studies conducted in China showed mixed results on the effectiveness of Jing Fang Bai Du san on Wind-cold syndrome. One study showed that it was no better than no treatment while another study showed that concentrated granules of Jing Fang Bai Du san was more effective (80%) than Western medicine (10%) in improving and resolving symptoms of Wind-cold syndrome within 7 days.
The Ying Qiao san can relieve external symptoms and effectively clear up the pathogenic heat. It contains 10 herbs: Fructus Forsythiae, LoniceraeFlos, Radix Platycodi, MenthaeFolium, GlycyrrhizaeRadix, Herba Schizonepetae, Sojae Semen praeparatum, Fructus Arctii, PhragmitisRhizoma and LophatheriHerba. From pharmacological studies, it showed anti-inflammatory, antipyretic, analgesic, anti-bacterial and antiviral actions. A clinical trial also showed the concentrated granules of Ying Qiao san was more effective (66.13%) than Western medicine (40%) in resolving the symptoms of Wind-heat syndrome within 1 week. These two CHM formulae have been used for many years and have not been associated with any serious adverse reactions. The common side effects are mild diarrhoea and headache.
Although there are some data from Mainland China suggesting the effectiveness of these two formulae for URTIs but most of these previous studies were observational and the few clinical trials were not placebo-controlled and of poor quality. Furthermore, results of trials from Mainland China may not be generalisable to the people in Hong Kong. Most previous studies on CHM focused on individual herbs, which is against the TCM principles as pointed out by the WHO. The WHO recommends that future clinical studies should attempt to integrate TCM diagnosis pattern with traditional CHM treatments. In this proposed study, the integrated TCM approach of using traditional formulae of multiple herbs, guided by the TCM diagnosis, will be used in a double-blind randomized placebo-controlled trial.
