Pharmacist censured for not warning of dangers of mixing medications

A former “pharmacist of the year” has been censured by the State pharmacy regulator after failing to warn a customer, who later died, about the dangers of mixing her prescribed medications.

Alice Parnell (77), of Old Knockmay Road, Portlaoise, died in hospital from heart failure weeks after being prescribed the antibiotic clarithromycin while she was also taking the blood-thinner Warfarin.

Portlaoise-based pharmacist Audrey Kingston “openly admitted” she failed to tell Mrs Parnell’s husband Kieran about the risks of combining the medications when he collected the anti-biotic, her solicitor told an inquiry.

It was also alleged that Ms Kingston, who was crowned “pharmacist of the year” two days after Mrs Parnell’s death on May 16th, 2019, failed to consult with the woman’s GP about the potentially interacting drugs.

A Pharmaceutical Society of Ireland (PSI) fitness-to-practice hearing was told that Mrs Parnell should have been warned by her pharmacist to get blood tests within three days of her prescription.

Dr Jay Sharma, a consultant endocrinologist, treated Mrs Parnell when she was admitted to Portlaoise hospital a week after taking the prescribed clarithromycin, under the brand name Klacid.

It was “impossible” to say how much of her rapid deterioration was down to any interaction with Warfarin, he told the hearing, and “very difficult” to pinpoint the exact cause of death.

A postmortem was not carried out on Mrs Parnell, whose heart, liver and kidneys were “not working properly”, the inquiry heard.

“There were many systems going wrong,” Dr Sharma said.

While the “deterioration” of Mrs Parnell’s rate of blood-clotting - measured by INR - was “one of the important factors here” it was “not the main or the only factor,” the consultant said, adding that blaming a high INR would be an “oversimplification of the facts”.

“The INR may have contributed to (Mrs Parnell’s) decline but I think the main factors were her deteriorating renal and cardio and liver function… all three vital organs were chronically impaired.”

Expert witness

Keith O’Hourihan, a Cork-based superintendent pharmacist called as an “expert witness”, said it was important for dispensing pharmacists to advise patients, or their carers, about the risks of mixing Warfarin with Klacid.

The interaction of the medications can cause Warfarin to “become more effective very quickly” and INR tests should be carried out on the patient “within three days” of combining both, he said. This would allow for the Warfarin dose to be “adjusted accordingly”.

While few patients suffer clinical interactions, Mr O’Hourihan said he deemed “all Warfarin patients to be potentially one of the few”.

“My experience in dealing with Warfarin patients is INRs tend to go out of range unexpectedly. They have to be managed,” he told the hearing.

“Each patient prescribed clarithromycin, if on Warfarin, should be checked within three days. That would be fairly standard.”

Mr O’Hourihan said it was the responsibility of pharmacists to “dispense medication safely” and to contact the prescriber - in this case, Mrs Parnell’s GP Dr Gerald White - if there is a query or an issue with a prescription.

While the prescriber “has primary responsibility”, pharmacists should not dispense medications which can adversely interact with other prescribed medications “unless there is a satisfactory explanation” from the prescriber, he added.

The allegations against Ms Kingston were “serious” and met a “threshold for poor professional performance” both separately and cumulatively, said Mr O’Hourihan.

Complex mix

Cross-examined by Mrs Kingston’s solicitor Maria Dillon, he accepted that Mrs Parnell was taking “quite a large number” of medications for her conditions and that managing these would have been “complex”.

Ms Dillon said Ms Kingston, the supervising pharmacist at Chemco Pharmacy at SuperValu shopping centre in Portlaoise, was dispensing Warfarin to 17 patients on a regular basis at the time of the allegations.

A number of issues including dehydration, lack of nutrition and certain foods and drinks can impact on the effectiveness of Warfarin, she said, as well as a “significant number” of medications.

Ms Kingston has had an “unblemished career” over 20 years in pharmacy and the allegations against her were “not representative”, Ms Dillon said.

She said Ms Kingston has addressed “any perceived deficits in her practise as a community pharmacist” including taking a course in anti-coagulation training run by the Irish Institute of Pharmacy at Queen’s University, Belfast.

Since qualifying, she has worked “without ever coming to the attention of the regulator,” Ms Dillon said.

Chemco director Chris O’Grady had complimented her “conscience and diligence” and highlighted the “stress and anxiety caused to Ms Kingston because of what happened to Mrs Parnell”.

‘Very sad event’

Patrick Leonard SC, legal assessor to the PSI, said the “backdrop to the allegations is a very sad event that ended up in the death of a much loved wife and mother” and “none of us can lose sight of that”.

The barrister advised the PSI to bear in mind Dr Sharma’s evidence that it was “very difficult to answer” whether Mrs Parnell’s high INR reading after combining Warfarin and Klacid was part of the number of factors leading to her death.

The PSI agreed to “censure” Ms Kingston, under the Pharmacy Act 2007, and accept “a number of undertakings” offered by Ms Kingston “which she affirmed orally and will provide in written form”.