Published: Dec 9, 2013
The recommended pain medication for patients with myocardial infarction may interfere with clopidogrel, and a new effort targets readmissions.
Morphine Gets in the Way of Clopidogrel
When morphine and clopidogrel were administered at the same time, the antiplatelet didn't work as well, potentially explaining the previously observed association between morphine and increased mortality in patients with non-ST-segment elevation acute coronary syndrome.
In a randomized, crossover trial, Bernd Jilma, MD, of the Medical University of Vienna, and colleagues gave 24 healthy individuals a 600-mg loading dose of clopidogrel followed by either placebo or 5 mg of morphine. The presence of morphine delayed resorption of clopidogrel, reduced plasma levels of its active metabolite to levels typically seen in intermediate or poor metabolizers, and impaired platelet inhibition.
"Co-administration of morphine and clopidogrel should likely be avoided, if possible," the researchers wrote in the Journal of the American College of Cardiology. "More potent P2Y12 inhibitors may provide greater efficacy when morphine is injected, but their interaction with morphine should be evaluated in further trials."
Audience: Pharmacy, Cardiology, Anesthesiology
ISSUE: The U.S. Food and Drug Administration (FDA) is recommending that health care professionals carefully consider the timing of spinal catheter placement and removal in patients taking anticoagulant drugs, such as enoxaparin, and delay dosing of anticoagulant medications for some time interval after catheter removal to decrease the risk of spinal column bleeding and subsequent paralysis after spinal injections, including epidural procedures and lumbar punctures. These new timing recommendations, which can decrease the risk of epidural or spinal hematoma, will be added to the labels of anticoagulant drugs known as low molecular weight heparins, including Lovenox and generic enoxaparin products and similar products.
BACKGROUND: Epidural or spinal hematomas are a known risk of enoxaparin in the setting of spinal procedures and are already described in the Boxed Warning and the Warnings and Precautions sections of the labels for Lovenox and generic enoxaparin products. However, these serious adverse events continue to occur (see Data Summary). To address this safety concern, FDA worked with the manufacturer of Lovenox, Sanofi-Aventis, to further evaluate this risk and to update the Warnings and Precautions section of the Lovenox label with these additional timing recommendations. The labels for generic enoxaparin products will also be revised accordingly, as will those of other low molecular weight heparin-type products.
It is important to note that all anticoagulants carry the risk of causing spinal bleeding when used in conjunction with epidural/spinal anesthesia or spinal puncture. We are continuing to evaluate the safety of other anticoagulants to determine if additional label changes are needed.
RECOMMENDATION: Health care professionals and institutions involved in performing spinal/epidural anesthesia or spinal punctures should determine, as part of a preprocedure checklist, whether a patient is receiving anticoagulants and identify the appropriate timing of enoxaparin dosing in relation to catheter placement or removal. To reduce the potential risk of bleeding, consider both the dose and the elimination half-life of the anticoagulant:
