Statins in liver disease?

A middle-aged patient arrives to his regularly scheduled clinic appointment looking for refills of his medication. His PMH includes HTN, hyperlipidemia, diabetes mellitus, obesity, and cirrhosis secondary to nonalcoholic fatty liver disease. His medications include antihypertensive and antihyperglycemic drugs in addition to atorvastatin 80 mg by mouth daily. At this time, you recall that statins have a risk for hepatotoxicity and are concerned whether it should be refilled at this time. What are the considerations for continuing statin therapy in this patient with known liver disease?

Elevation of liver enzymes is a well-known risk of statin therapy. Since the first statin was approved by the FDA in 1987, regular monitoring of liver enzymes to screen for elevations was routine practice. However, in 2012, the FDA revised the prescribing information for all statins to recommend serum aminotransferases be measured at baseline and then only thereafter if clinically indicated. There were primarily two reasons for this change:

“Sulfa” allergy cross-reactivity

Let’s start with a patient scenario.  A patient presents to the emergency room experiencing a heart failure exacerbation.  When entering the order for intravenous diuretics, you note that a cross-reactivity warning has popped up for a “sulfa” allergy.  What evidence is there for cross-reactivity between Loop diuretics and “sulfa” allergy and how should this affect your decision?

Vancomycin dosing and monitoring in hemodialysis

Let's start with a patient case.  A patient on hemodialysis (M/W/F) is admitted to the hospital with cellulitis who also meets sepsis criteria.  He has a history of an MRSA infection during a previous admission so you want to initiate vancomycin at this time.  The patient is 76 kg and still makes some urine.  What dosing strategy should you choose and when/should vancomycin concentrations be monitored?

Drug interaction between warfarin and acetaminophen?

The management of anticoagulant therapy is an important component of the treatment of various disease states. Maintaining the narrow therapeutic range required for the safe and effective use of warfarin is essential to avoid suboptimal dosing and adverse events. Numerous drug interactions with warfarin are present due to alterations in absorption, distribution, and metabolism.  The severity of interactions with warfarin varies greatly and dictates very different recommendations for management and monitoring. In the most insignificant interactions, no change in dosage or monitoring is necessary, whereas some interactions require a significant empiric reduction in warfarin dosage and close monitoring of INR.

Prevention of postherpetic neuralgia

An elderly patient is admitted to the internal medicine service with a diagnosis of herpes zoster infection in the typical dermatomal distribution.  The patient’s rash is currently not very painful (2/10) but she is concerned about long-lasting pain as her friend had pain from zoster that lasted for months.  What can we use to prevent the development of postherpetic neuralgia?

Postherpetic neuralgia is a common complication of herpes zoster infection and can be challenging to treat.  Drugs approved by the FDA to treat postherpetic neuralgia include pregabalin (Lyrica), gabapentin (Neurontin), and capsaicin patch (high-concentration patch - Qutenza).  Other medications that have been shown in randomized controlled trials to also reduce pain from postherpetic neuralgia include topical lidocaine, tricyclic antidepressants (eg. nortriptyline), opioids, and tramadol¹. 

No medication has been approved for the prevention of postherpetic neuralgia but here is the data on several agents that have been studied:

Is levalbuterol (Xopenex) more effective than albuterol?

The choice between levalbuterol and albuterol continues to be an area of contention for outpatients, in the emergency department, and those admitted into the hospital. Here is a brief explanation of the difference between the two products.