Licensed drug importer Hind Wing has initiated a recall of two batches of Dithrasal ointment which have been found to contain excessive levels of 1,8 dihydroxyanthraquinone (DHAQ), the Department of Health says.

The ointments - Dithrasal 1% Ointment (Registration No. HK44964, Batch No. 6A49) and Dithrasal 2% Ointment (Registration No. HK44963, Batch No. 345296) - are used for treatment of psoriasis and imported from Australia.

The Australian Therapeutic Goods Administration has instructed a consumer-level recall of the product.

High levels of DHAQ - a known breakdown product of the active ingredient in Dithrasal ointment - have been associated with the development of tumours in animal studies.

The department said while there is no scientific evidence of an association between DHAQ and the development of tumours in humans, the product is being recalled as a precaution to avoid any potential safety risk to consumers.

The ointments are supplied in 50g tubes. According to the importer, 393 out of 432 tubes of the 1% product imported have been supplied to the Hospital Authority, the department, some private doctors and pharmacies. Fifty of 72 tubes of the 2% ointment imported were sold to private doctors and pharmacies.

Hind Wing has set up a hotline (2541 6569) to answer enquiries. Doctors and pharmacists should stop administering or supplying the concerned batches.