GLASGOW, Scotland — Neil Macdougall has had Type 1 diabetes almost as long as he can remember. He wears a pump on his hip, the size of a mobile phone, that drips insulin into his body. It’s as precious and necessary to him as air.

Macdougall says he stays on top of his condition. But he’s worried about what happens after Brexit. Nearly all the insulin in Britain is imported, the bulk of it from Denmark. If Britain crashes out of the European Union in March without a deal for how to manage the withdrawal, drugs that keep him alive could suddenly be hard to get. Without insulin, Macdougall figures, he’d be dead in 48 hours.

“It’s all very well for politicians just sitting in ivory towers saying, ‘We will get through this with a bit of courage and a bit of hope.’ Courage and hope don’t control my blood sugar levels,” said Macdougall, 44, a telecommunications engineer who works in Glasgow.

Britain’s government is warning against stockpiling medicine, but with uncertainty over Brexit looming, some families are desperate to gather backup doses. (Reuters)

Britain is getting wobbly in the knees as it faces what was once unthinkable: leaving the E.U. with no deal, no transition period, nothing to replace a system that has provided frictionless trade for more than 40 years.

The British newspapers have been a little hysterical, revealing plans, for example, to evacuate the queen from Buckingham Palace in the event of mass riots in London stoked by empty grocery-store shelves. 

Hardcore Brexiteers dismiss it all as propaganda generated by “project fear” Europhile campaigners. But just because some fears may be exaggerated doesn’t make others less real. And growing numbers of patients, doctors, pharmacists and hospital administrators are worried about what a “no deal” Brexit could mean for medicines and medical supplies reaching this island nation.

There doesn’t appear to be appetite in Westminster for a cliff-edge Brexit. Parliament last week voted to assert that Britain should not leave the E.U. without a deal. Still, the current legal default position is that the country will exit the bloc on March 29, with or without a deal. 

Most analysts agree that a no-deal departure would be disruptive, at least in the short term. 

Overnight, Britain would lose its status as part of the E.U.’s single market and customs union, and it would become subject to third-country rules. Trucks carrying food and medicine could face new border checks. The Road Haulage Association, a transport industry body, has warned of “disastrous queues at ports” if Britain doesn’t exit smoothly with a deal.

For those who rely on lifesaving medicines, the thought of roads to and from ports turning into parking lots is distressing.

As with many sectors, health care is deeply integrated across Europe, with sophisticated “just-in-time” supply chains uniting the 28-nation bloc. Up to three-quarters of all the drugs used by Britain’s state-run National Health Services come from or through the E.U.

British officials have issued assurances that if the country were to leave without a deal, patients will continue to receive the drugs they need — even if that requires the government to prioritize medical supplies over food.

“Of course, medicines will be prioritized,” health secretary Matt Hancock told a parliamentary committee. “We have been through detailed, line-by-line analysis of the 12,000 licensed medicines in the U.K. to ensure there is a plan for the continuity for all medicines in the event of a no-deal Brexit,” he added.

As part of its no-deal contingency planning, the government has asked drug companies to stockpile six weeks’ worth of medicines on top of their normal supplies. It is looking into chartering planes to fly in medicines and adding capacity to various shipping routes across the English Channel. It has purchased some 5,000 refrigerators for medical storage needs. “I’ve become the largest buyer of fridges in the world,” Hancock told the BBC.

What the government does not want is for individuals to do their own hoarding. Officials have discouraged patients and pharmacists from stockpiling and told doctors not to write extra prescriptions. 

“Doing so risks shortages for other patients,” warned Stephen Hammond, Britain’s health minister tasked with Brexit planning. “If everyone does what they are supposed to, we are confident the supply of medicines will continue uninterrupted whatever the Brexit outcome.”

The problem is that public trust is in low supply as people watch their government and a divided, squabbling Parliament struggle to agree on a Brexit deal. 

“Fundamentally, we need to go beyond the government saying, ‘Don’t worry, we have a plan, but we can’t really tell you about it,’ ” said Robin Hewings, head of policy at Diabetes UK.

Mark Dayan, a policy analyst at Nuffield Trust, a health-care think tank, assessed that government preparations “would probably prevent . . . really widespread shortages immediately.” Still, he said, “People are probably right to worry.”

“It’s going to be very difficult to 100 percent guarantee that nothing goes wrong in such a chaotic and untested situation,” Dayan said. He noted that beyond testing medical supplies, a no-deal Brexit could contribute to rising medical costs if the pound falls, and could cause personnel shortages at hospitals abandoned by E.U. nurses, and more strain on the health-care system if British retirees living in the E.U. suddenly lose their European health-care benefits and return home for treatment. 

Some pharmacists have already reported drug shortages. 

“We are on the front line, and we see, on a day-to-day basis, people coming in, quite desperate to get medication,” said Amo Sohal, owner of Kitsons Pharmacy in Worcester, England. Sohal said he has noticed a sudden drop in the availability of anti-inflammatory painkillers and epilepsy medication. “I’ve been told, ‘No, there’s no stock available,’ ” he said.

Sohal attributed the fall in supply, at least in part, to no-deal anxieties. He said he has heard stories of patients and other pharmacies ordering in bulk because “no one really knows what’s going to happen.”

Macdougall, the Type 1-diabetes patient, is among those hoping to have extra medication on hand, just in case. He said he has had trouble filling his usual order of pump parts, though — a supply shortage he suspects has to do with stockpiling by others.

Diabetes has become one of the most high-profile conditions to be highlighted by Brexit jitters, in part because 99 percent of Britain’s insulin is imported, largely from the E.U. It also needs to be refrigerated, so it cannot sit indefinitely in traffic jams.

“People with diabetes feel a visceral sense of fear about losing access to their insulin,” Hewings said. While the physical response varies from person to person, “if someone stopped taking insulin on a Friday, then they would probably need to go to the hospital by Sunday.” 

It’s “genuinely bloody terrifying,” said James Patrick, 39, a writer whose 7-year-old daughter has Type 1 diabetes.

Patrick said he imagined that stockpiling insulin would be pretty much impossible. “Your doctor isn’t going to prescribe you a year’s worth. You can’t just buy it, because it is a controlled substance, and it’s not shelf-stable,” he said.

Some of the major pharmaceutical companies have outlined backup plans. Novo Nordisk, the Danish drug company that makes most of the insulin used in Britain, said it has more than doubled its stock and has reserved special airfreight slots between April and July so that it can fly insulin into Britain as needed.

“It never should have come to this,” said Allen Curtis, 42, a diabetic from Sunderland, England. “Medication should be the one thing that should never ever be affected by whatever is happening.” 

He is concerned about diabetics adjusting their diet so they need less insulin. He knows firsthand how important getting the exact dosage of medication can be. By the time he discovered he had diabetes, at age 27, it had advanced to the stage where he was partially blind, forcing him to leave his job. “People are limiting themselves because of the threat of a no-deal Brexit,” he said. “That’s dangerous.” 

Ultimately, people will be looking to Britain’s most high-profile diabetic: Prime Minister Theresa May.

After she received a diagnosis of Type 1 diabetes, May told Diabetes UK: “It does change your life in that you have to make sure you’ve got the right diet and that you’re managing your blood sugar levels, but, beyond making sure you’ve got that routine, you just get on with other things exactly the same.”

Britons are hoping that remains true after Brexit.