Superdrug is to run enhanced mental health checks on customers seeking Botox and fillers following advice from the NHS.
The health and beauty retailer now offers Botox for £99 and dermal fillers for £125 -£349 at its flagship store on the Strand.
Only customers aged 25 and over can purchase the procedures, which could be rolled out to other Superdrug stores across the country if the London trial proves popular.
Professor Stephen Powis, medical director of NHS England, wrote to Superdrug after its London Botox trial was announced to urge the retailer to treat customers "responsibly".
"Pressures on young people’s mental health are greater than they ever have been, with families and the health service too often left to pick up the pieces," Professor Powis said in a statement.
"The lack of tough checks on cosmetic surgery means that the public is dependent on businesses taking voluntary steps to get their house in order, leaving people avoidably exposed to dangerous practices. Businesses that take action to deal with people responsibly, work to prevent harm and set themselves a high bar for their practices should make others follow suit."
In a press statement, Superdrug said it has "always assessed a patient’s mental health" as part of an hour-long consultation before administering Botox and dermal fillers. Following the NHS England advice, it will now ask additional questions designed to find out whether a customer could potentially have body dysmorphic disorder (BDD).
If a customer appears to have BDD, they could be referred to a GP or mental health charity Mind, and a 14-day "cooling off" period can be imposed.
It is estimated that one in 50 people in the UK have BDD, but the NHS says this mental health condition is especially prevalent in younger people.
Superdrug's new mental health checks have been welcomed by Kittie Wallace, a trustee of the BDD Foundation, who told the BBC that fewer than 10% of people with the condition are satisfied by cosmetic procedures.
"It is important that these measures are in place [at Superdrug] to protect such individuals from potentially damaging and unnecessary procedures," Wallace said. "Although their anxiety might reduce temporarily, they will often find themselves fixating on another part of their body that they want to change."
However, Labour MP Liz McInnes responded to the news by calling for proper statutory regulation on Botox and dermal fillers. Though NHS England hopes that other outlets will follow Superdrug's lead and run enhanced mental health checks before administering them, they are currently under no legal obligation to do so.
McInnes tweeted: "This is good as far as it goes but we need proper regulation on Botox and other cosmetic procedures. I keep asking for a debate in #Parliament on this but none granted so far. Will keep trying."