Louise Mulholland was filmed by a reporter for BBC's Inside Out – posing as a customer – offering Melanotan from a Boldon salon.

In the programme, viewers will see a beautician tell the reporter it was a "natural product" that she mixed herself, and explain how one of her customers was brown just two days after injecting it for the first time. She is not shown selling it in the programme.

The TV investigation comes after a Gazette probe found a growing number of people are injecting themselves with Melanotan.

The tanning drug stimulates the body's production of melanin, which gives the skin its colour.

Users inject it into their stomach every day for about a week, or until they get their desired colour, then top up their tan with a regular jabs once a week.

But medical experts are worried about the long-term effects of the drug, which is not licensed for human use.

Despite it being illegal to sell Melanotan, the programme shows Ms Mulholland telling the customer she would accompany her for the first injection and sell her 30 injections for £155.

Ms Mulholland, whose website profile claims she has more than 15 years' experience as a qualified nurse, also offered to give the customer a "do it yourself" kit to take home with her.

When approached by the BBC, Ms Mulholland told reporters: "I, as a responsible medical professional, following initial promotion and marketing, decided not to sell this product and will not sell it at any point in the future."

This morning, Ms Mulholland told the Gazette that although she originally marketed the product, she never sold it.

* Inside Out will be on BBC One at 7.30pm tonight.