Anyone with a credit card can buy a "lethal combination" of drugs online, health inspectors have said as they called for the public to be better informed about the dangers of buying prescription drugs from unregulated websites.
The Care Quality Commission (CQC) said it was "worried" about the challenge of online prescribers operating from abroad, and outside their regulatory jurisdiction.
Peter Wyman, chairman of the CQC, told the Health and Social Care Committee that some websites appear to be British medical practices but are operating overseas.
He called for the public to be "very cautious" over such websites which are not regulated by the CQC or regulators in the devolved nations.
Mr Wyman told MPs: "We are very supportive of all of the convenience both to the medical practice and to the patients of being able to access online, we think this is a good thing, many GP practices do this as an adjunct to what they do actually in the consulting room, and that's terrific and we can inspect that in the way that we have always done it.
"There are a number of private sector specialist primary care providers and prescribers, and they are effectively operating the same way - they are under our jurisdiction, we have inspected them.
"We had a number of problems with many of them - those have largely been corrected although there are still some where we have some concerns, but we have the toolkit to be able to deal with them because everything that they are doing is registered with us and it's here in England. That's straightforward.
"The only bit that isn't quite straightforward in that scenario is where they are using pharmacists to do the prescribing, and that's outwith our remit, but we work closely with the General Pharmaceutical Council to deal with that.
"The thing that worries me much more than that - because that is all manageable even though there is some work to do - is that you can go online, you can very quickly find something that looks like a British medical practice, with possibly GMC (General Medical Council) registered doctors, that to the ordinary person looks perfectly reputable, but it's operating outside this country and not just outside our legal jurisdiction but also our practical jurisdiction, and that's a real challenge.
"If something looks like it's very English but it's actually in some faraway part of the world, you can't regulate it.
"Something the system needs to look at is that the end part of that is the prescribing of drugs and dispensing of the drugs.
"If that happens in this country, there are some opportunities to put some regulation in place at that point, but in practice these are overseas online prescribers just putting stuff in the post and it gets through.
"Candidly, anybody on the committee within five minutes could get any lethal combination of drugs that they want and they will be delivered the next day at home - all you need is a credit card - and that is hugely concerning and its outwith any capability of regulation to deal with it.
"There is an education process to put the public on notice that if something isn't CQC-registered or similar in devolved nations, then they should be very, very cautious.
"In my mind I can't see any other practical way of dealing with it because you can never regulate what happens on the internet in another country."
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