Britons are facing some of the “most severe” shortages of NHS medicines on record including common painkillers, epilepsy drugs and HRT, health leaders have warned, even forcing some patients with impaired digestive systems to skip meals.

The National Pharmacy Association (NPA) has warned that medicine shortages pose a “serious risk to patient safety”.

The Royal College of GPs has also raised concerns about the impact medicine shortages have on patients, GPs and pharmacists.

Both have highlighted long-lasting supply issues affecting Estradot, a hormone replacement therapy (HRT) for menopausal women, and Creon, a drug taken by people with pancreatic cancer and cystic fibrosis to help them digest food.

Both medications have had serious shortage protocols (SSPs) in place for between one-and-a-half (Estradot) and two years (Creon) – a new NHS record – and SSPs were recently extended by the NHS until 10 July. SSPs were introduced by the Department of Health as an emergency short-term measure to manage shortages.

Pharmacies say this is forcing some patients to ration medication and, in some instances, even skip meals because they have been unable to obtain supplies.

Bryony Thomas, 48, from Stroud, Gloucestershire, describes herself as a pancreatic cancer survivor. Along with other survivors, she expects to rely on Creon for the rest of her life because her pancreas does not produce the enzymes to digest food. She said she had been affected by the shortages for the past two years and has had to ration the drug, most recently nine months ago.

She would still be rationing, she added, were she not able to share medication with others through patient groups on social media.

“There was a three-month window where I couldn’t get hold of my enzymes [Creon], so I had to reduce what I was eating. You’d have a much smaller meal, you eat less protein, you eat less fat,” Thomas said. “If I get anything down to under a month [of supply] I start to panic.”

Her mother-in-law has also been making four-hour round trips to get her medication from the only pharmacy, in Crewe, Cheshire, where it is available. Thomas is calling for a central distribution mechanism to pool Creon supplies left by patients who have died. At the moment, those stocks are destroyed.

“It’s really stressful; you’re on the phone for just hours, you’re driving around [to visit pharmacies], and all the patients are having to do this day in, day out,” Thomas said.

Pharmacies have also been struggling to source a number of commonly dispensed medicines, including Ramipril, used to manage high blood pressure, along with painkillers such as low-dose aspirin and co-codamol.

The Middle East conflict has made supply chains more volatile although it is not the only factor driving shortages, the NPA said.

Lack of ingredients, manufacturing disruption, the UK’s smaller medicines budget compared with other EU countries, and in the case of HRT, changing prescribing habits all play a part. Prices of some drugs, such as paracetamol and cetirizine for hay fever, have increased as a result.

The NPA, which represents 6,000 independent community pharmacies in the UK, wants the government to convene an urgent taskforce including medicine manufacturers, wholesalers and clinicians to tackle the issues.

More than 1,000 GPs and pharmacists will meet in Birmingham at a new conference organised by the NPA this weekend to discuss, among other things, improved information sharing about medicines.

Pharmacists and GPs spend significant time managing the growing number of medicine shortages: pharmacists need to source scarce drugs, while GPs have to alter prescriptions to fit in with supply issues, causing patients inconvenience and worry.

Olivier Picard, a pharmacist who chairs the NPA, said: “Medicine shortages are becoming more frequent, lasting longer and causing increasing disruption for patients.”

“These shortages are some of the most severe the UK has experienced. It is deeply distressing to find patients who have travelled from pharmacy to pharmacy to find the medicines they need without success.”

He said shortages were “frustrating and worrying”, and that “in some instances they pose a serious risk to patient safety”.

Picard called on the government to amend legislation that prevents pharmacies from making substitutions to a prescription, where a safe alternative is in stock.

Prof Victoria Tzortziou Brown, president of the Royal College of GPs, said: “Medicine shortages can be frustrating for patients, GPs and pharmacists alike, especially when patients have to endure lots of back and forth to acquire a suitable alternative … It’s essential that when shortages occur, the underlying causes are quickly identified and resolved.”