Pregabalin entered category M in August, two months after NHS England announced the drug should be prescribed “in accordance with normal practice”.

Pregabalin prices in the drug tariff currently range from £1.87 for a pack of 56 25mg capsules to £4.17 for a pack of 56 300mg capsules. But contractors told C+D last week they are being forced to pay almost £20 per pack by wholesalers.

Responding to C+D’s coverage, HDA executive director Martin Sawer said: “It seems that the market shocks flowing from such a large price drop for such a big volume product have been playing out.”

“Not only will pharmacists be losing out in the short term, but so will wholesalers, as the market adjusts.”

“All players in the supply chain have a duty to avoid supply shortages,” he added.

Mr Sawer was commenting in response to the Pharmaceutical Services Negotiating Committee’s call for contractors to exert “maximum pressure” on wholesalers to match the reduction in pregabalin’s reimbursement price.

Numark also told C+D last week that price hikes are "are not unusual with molecules where there is sometimes a shortage in the market – wholesalers have to pay more for a limited amount of stock”.