The pharma company told Proactive all unexpired stock of four types of the drug was going to be removed from retailers as a "precautionary action" and investigations were ongoing.
READ: Walgreens and Rite Aid join CVS Health in discontinuing sales of popular heartburn drug Zantac
The UK Medicines and Healthcare products Regulatory Agency (MHRA) advised patients to continue taking their medication if the health risk of discontinuing it was greater than the potential risk presented by the contaminant.
The US Food and Drug Administration (FDA) announced last month that some stocks of Zantac, sold generically as ranitidine, possibly contained a nitrosamine impurity called N-nitrosodimethylamine (NDMA) at low levels.
NDMA is a known environmental contaminant, classified as a probable human carcinogen, and is found in water and foods, including meats, dairy products, and vegetables.
The American authority alerted healthcare professionals and patients to voluntarily recall over-the-counter ranitidine tables, while it keeps carrying out tests to assess their potential impact. Not all ranitidine products in the US have been recalled.
GSK shares were up 0.98% to 1,729.8p in mid-morning.
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