Title: Loperamide high – more than a fix for diarrhea.<br/>Author: Hong Kim<br/><a href='http://umem.org/profiles/faculty/526/'>[Click to email author]</a><hr/><p>
Loperamide is a peripheral mu-opioid receptor agonist that is found in over the counter anti-diarrheal medication. Following the trend of opioid abuse epidemic, loperamide has been promoted on online drug-use forum as a treatment for opioid withdrawal and as a possible alternative to methadone. At the same time, recreational use of loperamide has been increasing as an opioid alternative. Unlike therapeutic use of loparamide (2 – 4 mg), loraparmide abusers take supratherapeutic doses (e.g. 50 – 100 mg) to penetrate the CNS to produce opioid effects. </p>
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In published case reports, loperamide caused cardiac Na channel blockade (similar to TCA and bupropion) and K channel blockade, resulting in EKG changes including QRS interval > 100 msec with terminal R wave in aVR and QTc prolongation, respectively. Loperamide associated death has also been reported (autopsy finding), although the exact cause of death was not determined.</p>
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It is unclear if administration of NaHCO<sub>3</sub> can reverse the cardiac Na channel blockade as in TCA and bupropion as the clinical experiences have been limited.</p>
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Bottom line:</p>
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Clinicians should be aware of potentially lethal cardiac toxicity of loperamide abuse (Na and K channel blockade).</li>
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<fieldset><legend>References</legend>
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Wightman RS et al. Not your regular high: cardiac dysrhythmias caused by loperamide. Clin Toxicol 2016;54:454-458.</li>
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Eggleston W et al. Loperamide abuse associated with cardiac dysrhythmia and death. Ann Emerg Med 2016 <span style="color: rgb(0, 0, 0); font-family: arial, helvetica, clean, sans-serif;">Apr 26. pii: S0196-0644(16)30052-X. doi: 10.1016/j.annemergmed.2016.03.047. [Epub ahead of print]</span></li>
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