A no-deal Brexit presents risks to the NHS and care homes despite extensive government planning, a watchdog says.
The National Audit Office praised the government for the “enormous amount of work” that had been done but said there were still “significant” gaps.
The extra shipping capacity government was buying to bring medicines into ports other than Dover may not be completely ready by 31 October.
And there was no clear evidence the care sector was ready, the NAO said.
The report raises concerns the sector has not received enough government support.
The government has arranged the stockpiling of supplies for the NHS.
But for the care sector, which is fragmented in that it relies on 24,000 companies to provide services, no central arrangement has been made to stockpile equipment and supplies, such as syringes and needles, most of which come from or via the EU.
When it comes to medicines, however, the supply of which has been organised for both the NHS and care sectors, the report acknowledges the work that has been done.
This includes stockpiling six weeks’ supply of drugs and arranging for emergency supplies to be fast-tracked in – some drugs, including cancer treatments, have a short shelf-life and so cannot be stockpiled.
But the report says it is still not known exactly what level of stockpiling is in place.
More than 12,000 medicines are used by the NHS, and about 7,000 come from or via the EU.
The publication of the report comes after MPs attempted to block the government leaving the EU without a withdrawal agreement.
Legislation has been passed requiring the government to ask for an extension if a deal cannot be agreed.
Labour MP Meg Hillier, who chairs the cross-party Public Accounts Committee, said the report was “deeply concerning”.
“I’ve seen countless examples of deadlines missed and government failing,” she said.
“If government gets this wrong, it could have the gravest of consequences.”
Dr Layla McCay, of the NHS Confederation, which represents managers, said the planning had been detailed but the situation was still concerning.
She also warned it was the “unknowns and unknowables” that perhaps presented the biggest risk.
A Department of Health and Social Care spokesman said: “We want to reassure patients we are doing everything we can.”
He said the government along with industry had “mounted an unprecedented response in preparing for Brexit” with stockpiles “increasing by the day”.