Black cohosh, an herb that many women take to relieve hot flashes and other symptoms of menopause, may be linked with liver damage. Therefore, products containing this herb will in the future carry a warning, Britain’s drug regulator said on Tuesday.

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.”

Symptoms of liver problems include pain on the right side of the stomach just below the ribs, unexplained nausea, flu-like symptoms, dark urine and yellowing of eyes or skin.

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

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