Sajid Javid is being urged to change the law to let pharmacists alter prescriptions during medicine shortages, as it emerged that some women are travelling hundreds of miles to seek hormone replacement therapy products.

There have been acute shortages of some HRT products, which are used by about 1 million women in the UK to treat symptoms of the menopause.

Claire Anderson, the president of the Royal Pharmaceutical Society, said community pharmacists should be able to dispense substitute versions of medicines on prescription without having to contact the prescriber – typically a GP – every time.

Currently, the law in England stipulates they must provide only the exact prescription.

The proposed shake-up would also let pharmacists make changes to quantities, strength and formulation of HRT and other medicines dispensed.

“At the moment pharmacists cannot amend prescriptions for HRT, so have to refer women back to their GPs when a medicine is not available,” Anderson said.

“Enabling pharmacists to do so will save time for patients, pharmacists and doctors, as well as lessening the anxiety for women waiting for medicines.”

On Sunday Javid announced plans to appoint a HRT tsar to get to grips with the shortages. The number of HRT products prescribed in England has more doubled in the last five years, contributing to stocks running low, while manufacturers have reported supply problems.

Some women are sharing their prescriptions or travelling hundreds of miles to source products, and there are fears that some women may be becoming suicidal as a result of their symptoms going untreated.

Anderson said she welcomed Javid’s plan to recruit a HRT tsar, but she added: “With continued concerns from patient groups about medicines supply for people with other conditions, this appointment must be part of a wider government strategy to ensure patient access to medicines.”

She said: “Pharmacists spend many hours dealing with medicines shortages when we’d rather be talking to patients about their care. One solution would be to enable pharmacists to make minor changes to a prescription when something is out of stock. This is faster for patients and more efficient for the NHS.

“Difficulties in accessing HRT unfairly impacts women, affects their mental health and worsens health inequalities – this is an area that not only impacts our patients but also the health and care workforce.”

The Pharmaceutical Services Negotiating Committee (PSNC), which represents NHS community pharmacies in England, said demand was outstripping supply for a small number of HRT medicines, and longer, 12-month prescriptions were exacerbating the situation.

“Disruptions to medicines supply can fluctuate very rapidly and on a very localised basis,” a PSNC spokesperson said.

“The situation is very variable depending on demand, local prescribing and existing stock levels in pharmacies, and it is difficult to gain a snapshot of where supply is sitting as it is constantly moving through the supply chain.

“We know that some pharmacies are receiving HRT prescriptions from women and prescribers hundreds of miles away, but we don’t have anything to confirm whether there is any significant regional variation in supplies.”

Janet Morrison, the chief executive of the PSNC, said: “The current disruption to supplies of some HRT medicines appears to only be affecting a small number of medicines, and most pharmacies report that they are able to help women in need of medication quickly.

“The disruption appears to be being driven by sudden increases in demand for some medicines, and by some prescriptions being written for much longer periods than is usual.

“It is incredibly worrying for women if they are not able to access medicines that they rely on. Pharmacies teams know this, and they will do all that they can to help. In many cases, other formulations may be available, although this can take a little time for pharmacies to sort out as they will need to speak to your GP first.”

The Labour MP Carolyn Harris, a co-chair of the UK menopause taskforce, welcomed ministers’ promises to address the shortages.

She said: “The trouble with the menopause is for far too long women have not been listened to, women have been ignored, they’ve been prescribed and diagnosed with other conditions and the menopause wasn’t even considered.”