Although people give generally positive feedback about the procedure, skin experts are less convinced.

Sunday Young Post columnist and dermatologist Dr Leung Sze-kee accepts that the fish may help with diseases such as psoriasis, but says the relief is temporary.

'It may last a few months to a year - it's not a magic cure. Sometimes, in the process, bleeding may occur. In that case you need to worry about open wounds and the possibility of infection with hepatitis B and so on.'