A 20-year-old woman taking part in the hunger strike by Palestine Action-affiliated prisoners has been taken to hospital after protesters gathered outside the jail where she was being held to demand she receive urgent medical attention.

Qesser Zuhrah, who is being held at HMP Bronzefield in Surrey while awaiting trial, is on day 46 of her hunger strike.

Prisoners for Palestine, a prisoner-led collective in Britain, said the Prison Service was reported to have denied an ambulance entry into Bronzefield on Tuesday afternoon despite Zuhrah having been unable to stand and writhing in pain on her cell floor.

A spokesperson for the prison said: “All prisoners have full access to healthcare, including attendance at external medical facilities if needed.”

Zarah Sultana MP and friends and supporters of Zuhrah gathered overnight on Tuesday to demand she be transferred to emergency care. The Green party peer Jenny Jones later joined the protesters outside the jail warning that Zuhrah’s condition could be life-threatening.

An ambulance eventually arrived to take her to hospital on Wednesday afternoon.

Prisoners for Palestine said Zuhrah had reported severe chest pain, breathlessness and abdominal and lower back pain.

It claimed her vital signs had been taken only intermittently and she had received inadequate electrolytes since returning from hospital on Friday, due to HMP Bronzefield reportedly running out of electrolytes.

According to a letter sent by lawyers for the hunger strikers, the previous hospitalisation came after Zuhrah spent a night begging for an ambulance, having collapsed and drifted in and out of consciousness.

She is one of two prisoners, along with Amy Gardiner-Gibson, also at Bronzefield, who have been refusing food for 46 days – the same amount of time as Martin Hurson when he became the sixth of 10 IRA hunger strikers to die in 1982.

The other prisoners taking part are Heba Muraisi (day 44), Teuta Hoxha (day 38), Kamran Ahmed (day 37) and Lewie Chiaramello (day 12), who has diabetes.

All are being held for alleged involvement in Palestine Action protests and will have spent well over a year in jail – the pre-trial custody time limit is six months – before being tried. Their demands include immediate bail, ending the ban on Palestine Action and stopping restrictions on their communications.

On Wednesday, the former Labour leader Jeremy Corbyn asked Keir Starmer at prime minister’s questions whether he would meet representatives of the hunger strikers. Starmer declined, echoing the response of the justice minister Jake Richards when Corbyn asked him the same question 24 hours earlier.

An HMP Bronzefield spokesperson said they could not provide information about specific individuals, but added: “Any prisoner refusing food receives regular medical assessment and support from clinicians, as well as being offered mental health support.”

The spokesperson said prisoners were managed in line with policies and procedures governing the entire UK prison estate, including assessment of individual risks and security status, and that they could raise specific complaints directly with the prison.

Central and North West London NHS foundation trust, which is responsible for commissioning healthcare within the prison, referred the Guardian to the Ministry of Justice.

An MoJ spokesperson said: “Prisoners’ wellbeing is continually assessed, and appropriate action is taken, including hospital treatment where required.

“His Majesty’s Prison and Probation Service (HMPPS) has assured ministers that all cases of prisoner food refusal are being managed in accordance with the relevant policy, and with appropriate medical assessment and support – consistent with prisoner rights.”