Health experts are reminding consumers undergoing laser hair removal of the need to avoid the sun afterwards, as this could damage the skin.
People who do not follow the advice could suffer burning, scarring, blisters or changes in skin colour, according to health campaigners at Which?
While reputable private clinics will undoubtedly inform patients of the risk when they undergo laser hair removal, there are concerns that unlicensed clinics, of which there are around 3,000 in the UK, may not be so cautious.
David Gault, a consultant plastic surgeon at London's Portland Hospital, said: "When you have laser hair removal the laser itself targets the pigment in your hair in order to destroy it.
"Unfortunately, when the skin is tanned, the deeper melanin colour of the skin can also become a target."
Mr Gault explained that patients' skin could therefore become patchy and mottled.
Which? spokeswoman Frances Blunden said: "If you are having laser hair removal treatment, make sure the clinic is licensed and the practitioner properly qualified.
"Otherwise, you could be putting yourself in the hands of untrained staff who don't explain all the possible risks."
Independent advice on private healthcare