Coroner raises concern over prescribing errors following prison death

A coroner has raised concerns over the potential for prescribing errors at a London prison after a prisoner died from a cardiac arrest following an epileptic seizure.

In a ‘Prevention of future deaths’ report’ (PFD), published on 13 April 2026, Jenny Goldring, coroner for inner south London, stated that Mark Robert Smith, aged 47 years, died at HMP Thameside, Greenwich, in January 2019.

Although his cause of death was cardiac arrest as a result of an epileptic seizure, the coroner also noted that, while not a direct cause of Smith’s death, a “significant contributing factor” was “toxicity related to pregabalin and sodium valproate level in someone with epilepsy together with a decline in physical and mental wellbeing”.

The coroner wrote that before Smith’s arrival at HMP Thameside on 8 January 2019, he had a documented history of asthma, epilepsy and depression. In addition, Smith was already prescribed pregabalin, dosulepin and sodium valproate, the coroner said.

“All medication was maintained by the prison GP as before, with the exception of co-dydramol, which was replaced by an as-and-when required dose of diazepam, and a change of route for pregabalin administration from tablet to liquid, on a dose of 50mg per day for the first 7 days of prison admission, increasing to 100mg per day thereafter,” the coroner said.

“There was a conflict between the pregabalin prescription shown on Systm 1 prison medical records (3,100mls across 29 days), and the 50mg per dose recorded on the administration records. There was a failure to correct the prescription on Systm 1 despite it appearing a minimum of 6 occasions.”

She also said that on 17 January 2019, Smith was taken to Queen Elizabeth Hospital, Woolwich, after the prison GP observed “high temperature, tachycardia, sweating and generally delirious presentation”.

“His medication upon arrival was kept to the same plan as prison, including the increase in pregabalin dose to 100mg,” the coroner said, adding that, while at the hospital, Smith was administered 2.5ml of liquid pregabalin twice per day”.

On 23 January 2019, a member of prison healthcare staff raised concerns about Smith’s condition and requested a multidisciplinary team (MDT) meeting with Queen Elizabeth Hospital ahead of Smith’s discharge back to prison, which did not take place, the coroner said. Smith was then discharged back to HMP Thameside on 28 January 2019.

The coroner said that Smith was readmitted to hospital on 30 January 2019, after being observed to be having seizures on and off for three to four hours.

“During this admission at Queen Elizabeth Hospital, Mark was administered 2.5ml of liquid pregabalin twice daily,” the coroner wrote.

She added that Smith was discharged from Queen Elizabeth Hospital back to HMP Thameside on 4 February 2019, although staff were “not adequately prepared for Mark’s return due to insufficient briefing and a declined MDT meeting”.

Following his return to prison, Smith’s condition deteriorated rapidly, and he was kept on 15‑minute observations, the coroner highlighted.

The coroner noted numerous checks were either missed or falsely recorded. She also said that there was “an inadequate handover” between day and night healthcare staff.

Smith was pronounced dead at 00:38 on 6 February 2019, after staff were unable to revive him. The coroner said that the defibrillator retrieved from the prison management office did not have batteries or pads.

“The nature and extent of medical care and clinical observation by prison healthcare staff between 5 and 6 February [2019] possibly made a material contribution to Mark’s death,” the coroner wrote.

The coroner said: “The inadequacy of handover and basic observation, and failings in sufficient record-keeping by the prison healthcare staff during the evening of 5 February [2019] after 20:30 meant that signs and symptoms of an epileptic seizure were not observed and, therefore, an opportunity to perform life-saving measures in either administering medication to stop the seizure and/or, ultimately, timely CPR, was missed.

“Mark was administered doses of liquid pregabalin of more than 2.5 mL by healthcare staff while at HMP Thameside, and this probably made a material contribution to Mark’s death.”

“On the balance of probability, this is the most likely cause of the levels of pregabalin seen in the toxicology postmortem results,” she added.

Under her concerns, the coroner wrote: “The wrong dose of medication could be prescribed and/or administered with life threatening consequences.”

She noted that she had although she had seen “evidence of significant improvements in the healthcare provision at HMP Thameside since 2019 … as recently as 2024 to 2025 HMIP [HM Inspectorate of Prisons] and IMB [independent monitoring board] reports noted ‘significant risks with management of medicines’ and ‘prescribing errors’. 

“Whilst recent internal audits in 2025 show significant improvements, medication incidents (datix) are recorded in late 2025, and the principal pharmacist notes a very busy site with multiple prescriptions screened daily,” the coroner added.

The coroner also wrote: “Further, during the inquest it proved difficult to establish how Systm 1 (the medical note system) operated and whether there were risks inherent in the system itself. For example, it was suggested the system would convert mg into ml or pre-populate entries such as 100 ml, in contradiction to the subsequent PFD evidence provided.”

The coroner’s report was sent to prison healthcare supplier Practice Plus, the chief executive of Lewisham and Greenwich NHS Trust, the director at HMP Thameside and director general/chief executive of HM Prison and Probation Service, all of whom have until 3 June 2026 to respond.

In a statement to The Pharmaceutical Journal, a spokesperson for Practice Plus said: “We took over healthcare at HMP Thameside in 2023 and have ensured that any learnings arising from Mr Smith’s tragic death have been addressed.

“Across all of our prison healthcare services, we have layers of checks and safeguards in place to ensure safe and accurate prescribing of the medicines on our formulary, including on site where prescriptions are checked by a clinical pharmacist and a registered pharmacy technician. We very rarely prescribe liquid dosages of any drug, and pregabalin — which has since become a controlled drug — is only ever given in tablet form.”