Polypharmacy and Drug Interaction

  • Christopher A. Steel
  • Jill Eckert


In days past, a basic understanding of a drug’s mechanism of action was sufficient for the purpose of prescribing a medication to treat the vast majority of patients and their conditions. Those days are long gone with 48 % of Medicare beneficiaries over the age of 65 having three or more chronic medical conditions and 21 % having five or more of these conditions (Boyd et al., JAMA. 294(6):716–24, 2005). It has been estimated that the likelihood of a drug interaction in a patient taking only two different medications is only 6 %, whereas when the number of medications increases to ten, the likelihood of drug interaction increases to 100 % (Lin, Can Alzheimer Dis Rev. 10–4, 2003). With this virtual certainty of frequently dealing with drug interaction, a physician must have a solid understanding of polypharmacy along with drug interactions.


Oral Contraceptive Valproic Acid Sexual Dysfunction Hepatic Failure Neuroleptic Malignant Syndrome 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© American Academy of Pain Medicine 2015

Authors and Affiliations

  1. 1.Department of AnesthesiologyPennsylvania State University Milton S. Hershey Medical CenterHersheyUSA
  2. 2.Pennsylvania State University College of MedicineHersheyUSA

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