The Food Safety Centre says four types of Anlene vitamin-K enriched milk products may affect patients taking blood thinning drug Warfarin.

The centre's Principal Medical Officer (Risk Management) Dr Tina Mok today said New Zealand authorities have issued a statement explaining the possible impact of the products on patients taking Warfarin.

Noting the products themselves are not problematic for normal people, she said they do not need to be recalled.

Dr Mok said the importer has confirmed that the concerned products are for adult consumption and warning labels will be added to them.

The centre has informed the Department of Health, the Hospital Authority and doctors of the matter. The centre will monitor the situation.