A "game changer" weight loss injection used by celebrities including Twitter boss Elon Musk is to be made available through the NHS amid warnings that the drug is not a "quick fix".
In a "pivotal moment", thousands of people living with obesity in England are set to be offered Wegovy, also known as semaglutide, on prescription after health officials approved its use.
Last October, Musk was asked by a Twitter user on the platform what his secret was to looking "fit, ripped, and healthy" to which he replied "fasting" and "Wegovy".
Patients on the NHS will inject themselves weekly using a pen and the drug works by making people feel full, meaning they eat less and lose weight.
It suppresses the appetite through mimicking the hormone glucagon-like peptide-1 (GLP-1) which is released after eating.
A previous study found people who were given the medicine saw their weight drop by 12% on average after 68 weeks.
Another study said side-effects included nausea and diarrhoea but these were typically mild-to-moderate in severity and subsided with time.
Adults with at least one weight-related condition and a body mass index (BMI) score of at least 35 would be eligible for the drug, which is made by Novo Nordisk.
Such conditions include type 2 diabetes, prediabetes, high blood pressure, dyslipidaemia (unbalanced or unhealthy cholesterol levels), obstructive sleep apnoea and heart disease.
Those with a BMI of 30 and over may be able to access the drug in some cases.
People will only be given Wegovy on prescription as part of a specialist weight management service involving input from several professionals, and for a maximum of two years.
It is to be used alongside a reduced-calorie diet and increased physical activity, stated the National Institute for Health and Care Excellence (Nice), which approved it.
Nice's Helen Knight said: "For some people losing weight is a real challenge which is why a medicine like semaglutide is a welcome option.
"It won't be available to everyone. Our committee has made specific recommendations to ensure it remains value for money for the taxpayer, and it can only be used for a maximum of two years."
Professor Nick Finer, from the National Centre for Cardiovascular Prevention and Outcomes at UCL, said: "The efficacy of semaglutide is a true game changer for the medical treatment of obesity, a chronic disease that shortens life through its many complications."
And Alex Miras, professor of endocrinology at Ulster University, said: "This decision made by Nice is a pivotal moment for the treatment of people living with obesity.
"The weight loss that can be achieved with this safe medication is substantial and likely to lead to the improvement of obesity-related complications in a large number of patients."
But Dr Stephen Lawrence, associate clinical professor at the University of Warwick, cautioned: "It is important to note, however, that this medication is not a quick fix or a replacement for following a healthy lifestyle, which includes regular physical activity and healthy eating."
In February, it emerged that some high street chemists in England will prescribe the drug, if suitable, through their online doctor services.
A spokesperson for Novo Nordisk said: "Novo Nordisk welcomes the final Nice recommendation for Wegovy (once-weekly semaglutide 2.4mg), as an option for weight management within the NHS.
"We are working to make Wegovy available in the UK as soon as possible."