How safe are these herbal medicines?

Close on the heels of the Canadian government warning against the use of Indian herbal remedies, Britain's healthcare agency has said herbal remedies available in the country may contain dangerous levels of heavy metals.

The Medicines and Healthcare Regulatory Agency said these products, made by Indian companies, may have entered the British market and advised consumers not to take any of those listed by it.

The suspect medicines and the companies include Sudarshan tablets made by Zandu Pharmaceuticals, India, Shilajit capsules made by Dabur India Ltd, Safi liquid made by Hamdard Wakf-India, Karela capsules made by Himalaya Drug Co, India and Charantia, UK, Times newspaper reported on Thursday.

Also read: Are herbal supplement healthy?

Following the warning by the Canadian government in July, the Indian government had sought details of the analysis carried out by the Canadian health regulator and directed companies to carry out safety/toxicity studies for the banned products through the National Accreditation Board of Laboratories.

"Medicinal products containing high levels of heavy metals pose a serious public health risk. Many of the products we suspect to have entered the UK may contain mercury, arsenic and lead. These metals cause severe nausea, vomiting and abdominal pain. Other serious problems such as kidney damage, convulsions and coma have been reported," Roy Alder, the British agency's director of executive support said.

The agency advised consumers to be vigilant and aware of the potential side effects of these herbal medicines.