People are being warned to stop using a weight loss pill sold over the internet and in Chinese medicine shops.
The Medicine and Healthcare products Regulatory Agency (MHRA) has issued a warning about Herbal Flos Lonicerae (Herbal Xenicol). Anyone taking the product should stop immediately and contact a doctor, it says.
The warning comes after reports of side effects such as palpitations, with one patient needing hospital treatment. The capsules are thought to contain an as yet unknown pharmaceutical substance.
Tests are underway to establish the cause of the side effects.