BEIJING - To deter illegal drug production, China's drug authority now requires pharmacies to check and register the identity cards of people purchasing medicines containing ephedrine.

The maximum amount of each purchase will also be strictly limited, the State Food and Drug Administration (SFDA) said in a statement issued Tuesday.

The SFDA has launched a five-month national campaign aimed at limiting the sales of medicines that can be used to make illegal drugs, and medicines containing ephedrine ingredients will be a focus, the statement said.

The administration also ordered better supervision over the wholesale of ephedrine-containing medicines to control the spread of these medicines.

Moreover, the campaign efforts will include intensified supervision over pharmaceutical enterprises and stricter market admittance for ephedrine-containing medicines.

The authority will revoke the licenses of pharmaceutical enterprises found in violation of the ephedrine control regulations and those that are responsible for medicines being used for illegal purposes, said Wu Zhen, deputy head of the SFDA.

Ephedrine is commonly used in medicines to ease common cold symptoms, such as coughing, runny nose and nasal congestion, but it can also be extracted for producing methamphetamine hydrochloride, or crystal meth.

As the production and sale of ephedrine remain under the government's strict control, medicines containing ephedrine ingredients have become an alternative for criminals manufacturing drugs.

In 2010, police in Hangzhou, capital of east China's Zhejiang Province, cracked a case in which suspects bought over 1.3 million units of nasal drops and other medicines containing ephedrine, then transported these materials to Southeast Asia to produce drugs.