The China Food and Drug Administration (CFDA) Wednesday said no illegal ingredients have so far been detected in an oral medicine after warnings from a Hong Kong health authority that it may contain dangerous substances.

Initial tests showed that illegal additives of phenacetin and aminophenazone have not been found in the same batch of the drug that was identified by Hong Kong's Department of Health on Tuesday, said the CFDA.

The oral drug, or "Vitamin C Yinqiao" tablet, one of the most commonly used cold medicines in China, is produced by Shenzhen Tongan Pharmaceutical Company, based in south China.

Laboratory tests on the product found the presence of two undeclared and banned western medicines, phenacetin and aminophenazone, according to statement released by Hong Kong's Information Services Department Tuesday.

However, the ingredients listed on the bottle, including vitamin C, paracetamol and chlorpheniramine maleate, were not detected, the statement said.

The CFDA contacted Hong Kong's health authority to find out more about the drug on Wednesday and ordered the company to suspend its sale.

Further tests are being carried out on other batches of the drug, and relevant information will be released as soon as possible, according to the CFDA.

The CFDA said "harsh measures" will be imposed on the manufacturer if illegal practices are found.

(Xinhua News Agency June 19, 2013)