Diabetics and insulin distributors are nervously stockpiling caches of insulin in order to protect against shortages as they confront the prospect of Britain exiting the European Union without a withdrawal agreement.

37 year old teacher David Burns is based in London. David is among the 3.7 million diabetics resident in the UK who are reliant on the synthetic hormone, which regulates their blood sugar levels.

David: "All of these come from Switzerland, these come from Denmark, but we don't make any of this here and none of these

companies that made this are British - I think the vast majority of them are Swiss."

Under a no deal Brexit scenario, longstanding customs agreements and medical controls would cease and require re-constituting. This could precipitate backlogs and holdups in the importation of vital pharmaceutical drugs, endangering patients' lives.

To allay public concerns, the Department for Health has drafted contingency plans for expediting emergency medicine shipments to offset any congestion arising at the border. David, however, remains apprehensive.

David: "If I ran out of insulin, obviously I don't want to test this out, but I can't imagine I'd have more than a couple of months left on this planet, so I'm terrified of a no-deal Brexit."