Antibiotic Failure: Iron and Levaquin Drug Interaction – Case Study

44 year old male with a history of respiratory issues.  Recently diagnosed at the clinic with pneumonia.  Levaquin (oral) was initiated for a 10  day period.

Current medication list includes:

  • Advair 250/50 twice daily
  • Albuterol as needed
  • Hydrochlorothiazide 25 mg daily
  • Ferrous Sulfate 325 mg twice daily
  • Prilosec 20 mg daily

Day 7 of 10 for the Levaquin course and the patient is not improving.  He presents to the clinic for reassessment of pneumonia and requests a different medication.  A Zpak is prescribed and within 3-5 days the patient begins feeling much better with a full resolution of the pneumonia following treatment with azithromycin.

So, what happened?  We can only speculate, but I’ve got three major points that I think could’ve been the problem.

1.  Assessment of adherence is critical with antibiotics and any medication for that matter – that is where I would start.

2.  Resistance to antibiotics is a significant problem and could be at play here.

3.  I’ve seen this happen several times, and I think it might lead to failure more often then we realize especially with quinolone antibiotics.  The iron and Levaquin drug interaction is well known, but does slip through the cracks, especially with polypharmacy complicating things.  Iron can significantly block absorption of Levaquin leading to low concentrations in the blood and potentially low enough to cause failure of treatment.  Again only speculation, but this is an interaction you should be aware of and frequently assess for use of products with iron, calcium, and magnesium which can all bind up Quinolones.

Here’s another Levaquin interaction you should know!

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Written By Eric Christianson

December 14, 2014

Free PDF – Top 30 Medication Mistakes

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