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Guild critical of Medsafe's risk assessment
28 May 2010
As the Atenolol recall saga continues, Medsafe has released details on the overweight and underweight tablets and their clinical significance.
However, the Pharmacy Guild is critical of the risk assessment and says the information is not detailed enough to explain the recall.
Derek Fitzgerald, Medsafe manager for compliance management, says the overweight Pacific Atenolol 50mg tablets, which were the subject of the initial recall on 13 May 2010, were found to contain 86 to 88mg.
At the time the recall was initiated, he says five tablets in the batch had been identified in this range. In some cases, more than one overweight tablet was found in a single bottle.
The cause of the problem was unknown and, therefore, the likely frequency of overweight tablets was unknown.
“The dose-response curve for Atenolol is such that an increase in the 50mg to 100mg range is significant with respect to therapeutic effect and possible side effects. Medsafe considered that a significantly higher dose administered to a patient stable on 50mg could result in an unexpected drop in blood pressure possibly resulting in, for instance, postural hypotension, fainting, etc. For instance, a fall for an elderly person experiencing unexpected low blood pressure could have serious consequences,” he says.
With the second recall on 27 May, which was triggered through reports relating to smaller tablets, Medsafe says it again considered the magnitude of the deviation from specification and the possible consequences were unacceptable.
The agency says 17 tablets over four batches of the 100mg tablets had been measured and determined to contain doses ranging from 77mg to 86mg; and for the 50mg tablets, four tablets in five batches that contained underweight tablets varied from 31mg to 41mg. All of these tablets were found in two batches that had been distributed.
“These figures (as with those determined for the 100mg overweight batch) relate to a very small sample of tablets from the batches and were only obtained by visual sorting and subsequent measurement; with the possibility that some tablets with significant variations could have been missed,” Mr Fitzgerald says.
He says although sampling was limited, instances were detected where more than one tablet was found in a single bottle indicating there was an increased possibility for a patient to receive consecutive underweight or overweight tablets.
“Overall, the results indicated a widespread, significant problem for both strengths of the product. Under-dosing is likely to result in under-treatment with the potential for, for instance, severe exacerbations of arrhythmias, angina or potential for myocardial infarction.”
Mylan undertook a risk assessment regarding the underweight issue in which it concluded:
• There is an unknown, but real risk of a patient with underlying cardiovascular disease taking one or more underweight Atenolol tablets.
• If several underweight tablets are taken consecutively by a patient using Atenolol to manage angina pectoris or an arrhythmia, they may experience a sudden decrease in plasma concentrations of Atenolol, a loss of beta-blockade and a subsequent withdrawal reaction.
• Withdrawal reactions may include severe exacerbation of angina, myocardial infarction or arrhythmias.
• Consequently, there potentially is an unacceptable risk to the patient.
“Medsafe concurs that there is a real risk to a patient’s health. These conclusions are consistent with the established criteria for a recall of a medicine to consumer level,” Mr Fitzgerald says.
However, Pharmacy Guild chief executive Annabel Young says this isn’t a risk assessment at all.
“Saying something could happen is not sufficient. They mention some possible consequences of patients being over or under medicated but they do not actually calculate the risk of this happening.
“What is probability of each of the series of events that has to happen, and what is the cumulative probability that all the events will happen, before a serious adverse event might actually happen? Only when they know this probability can they work out whether a recall is warranted.
“I am staggered that this is all that they can produce as the basis of a significant recall that has impacted on patients (convenience and cost), caused massive additional work for pharmacists and imposed costs on the medicines supplier.”
Comments
So, based on Ms Young's synopsis, and knowing that underweight medication has been dispensed, her preferred option would be to wait for patients to present with serious complications and/or heart failure, before the the matter is deemed serious enough for a recall.
Congratulations to Derek Fitzgerald. Patient safety should always be the paramount concern - not dollars.
Someone PLEASE explain to Annabel Young that it's up to clinically trained people to decide whether such a recall is warranted or not, not lawyers like herself.
And tell her there's actual real-life patients involved, not just numbers in a paper trail.
Why does she raise these nonsense clinical statements when she knows nothing? Does she not have pharmacists advising her about this kind of thing before she opens her mouth??
Someone PLEASE explain to Annabel Young that it's up to clinically trained people to decide whether such a recall is warranted or not, not lawyers like herself.
And tell her there's actual real-life patients involved, not just numbers in a paper trail.
Why does she raise these nonsense clinical statements when she knows nothing? Does she not have pharmacists advising her about this kind of thing before she opens her mouth??
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