Black cohosh, a herb popular for relieving hot flashes and other symptoms of menopause, may be linked to liver damage, European regulators warned on Tuesday.

The European Medicines Agency said people should stop taking the herb immediately if they had any symptoms suggesting liver injury, such as tiredness, loss of appetite, yellowing of skin and eyes, severe upper stomach pain with nausea, or dark urine.

In Britain, the Medicines and Healthcare products Regulatory Agency (MHRA) said a review of all available data had concluded that liver injury resulting from black cohosh was rare but could be serious.

“In the light of this advice, the MHRA is working with the herbal sector to ensure that labels of black cohosh products carry updated safety warnings,” Professor Kent Wood, the agency’s chief executive, said in a statement.

“The labels will point out the possible symptoms so that appropriate action can be taken without delay.”

The warning will come as a blow to women looking for a product to ease the symptoms of menopause who may have assumed that black cohosh, as a herb, was a safe option.

The herbal treatment has been used for many years in Europe and North America and gained popularity after a highly publicised study in 2002 found hormone replacement therapy raised the risk of heart attack, stroke and breast cancer.

Black cohosh is used in a range of licensed and unlicensed products across Europe. In addition to treating menopause symptoms, in some countries it is also used for rheumatic pain, cough, stomach cramps and period pains.

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