Tips for Managing Adverse Drug Reactions

Adverse drug reactions (ADRs) are a leading cause of morbidity and mortality, accounting for up to 30% of hospital admissions in the United States,¹ and costing approximately $170 billion annually.² Elderly patients are at highest risk of experiencing ADRs, many of which are preventable.¹ The most commonly-implicated medications include antibiotics, anticoagulants, digoxin, diuretics, hypoglycemics, antineoplastics, and nonsteroidal antiinflammatory drugs, which are responsible for about 60% of hospital admissions.¹

Actual, perceived, or even fear of ADRs increases the likelihood for medication nonadherence, leading to suboptimal treatment efficacy and adding to the burden of disease.^1-3 Actual ADRs can result from medication pharmacology, whereas perceived or fear of ADRs are influenced by psychological factors such as predetermined medication views, lack of belief in treatment necessity, anticipation of ADRs, conditioning based on past experiences, and misattributing symptoms as ADRs.^1-3 Clinician awareness of these factors will help to reduce risk for ADRs and optimize management, ultimately allowing patients to benefit from intended treatment.

The American Society of Health-Systems Pharmacists (ASHP) provides guidelines and emphasizes the role of pharmacists in comprehensive ADR management.⁴ Here are some tips:^4-6

Risk Minimization

• Understand patient views about medication therapy.
• Educate about the benefits of treatment.
• Inform patients about potential ADRs and management strategies should any occur.
• Ensure an updated and accurate medication list.
• Utilize decision support software to help prevent ADRs.
• Start with low doses and frequencies and slowly titrate as tolerated.
• Initiate less-potent agents, agents with direct mechanisms of action, or alternatives with lower adverse event incidence.
• Avoid or reduce the use of interacting medications.
• Prescribe dosage forms with minimal systemic exposure (eg creams, patches).

Recognition, Detection

• Be familiar with known ADRs of the medication as well as the patient’s pre-existing symptoms.
• Evaluate new symptoms as possible ADRs, looking into health conditions, labs, or other factors which may explain the symptoms.
• Consider the temporal relationship between medication initiation and symptom onset.
• Challenge concepts like stopping the medication to see if the symptom subsides in absence of the medication, and restarting to see if symptoms return.
• Utilize lab tests for more evidence to identify an ADR.
• Apply probability tools^7-9 such as the Naranjo Adverse Drug Reaction Probability Scale or 4Ts for heparin induced thrombocytopenia.¹⁰
• Express empathy and maintain a trusting relationship with the patient.
• Reduce dosing or discontinue the offending medication.
• Switch to another agent or dosage form less likely to cause ADRs.
• Treat side effects when necessary (beware of prescribing cascades).
• Document the ADR in the patient’s medical record.
• If working from a care setting separate from pharmacy, notify the patient’s pharmacy to document the ADR in the pharmacy records.
• Report ADRs through appropriate channels such as your organization’s reporting system, the drug manufacturer, FDA MedWatch¹¹ or Vaccine Adverse Event Reporting System.¹²
• Track and trend ADRs for ongoing process improvement.

References

• Leporini C, De Sarro G, Russo E. Adherence to therapy and adverse drug reactions: is there a link? Expert Opin Drug Saf. 2014;13(Suppl 1):S41-S55
• Heller MK, Chapman SC, Home R. Beliefs about medication predict the misattribution of a common symptom as a medication side effect---Evidence from an analogue online study. J Psychosom Res. 2015;79(6):519-29.
• Leporini C, Piro R, Ursini F, Maida F, et al. Monitoring safety and the use of old and new treatment options for type 2 diabetic patients: a 2-year (2013-2016) analysis. Expert Opin Drug Saf. 2016;15(sup2)17-34.
• American Society of Health-Systems Pharmacists. Guidelines. ASHP Guidelines on adverse drug reaction monitoring and reporting. http://www.ashp.org/DocLibrary/BestPractices/MedMisGdlADR.aspx.
• Brahma DK, Wahlang JB, Marak MD, Sangma MC. Adverse drug reactions in the elderly. J Pharmacol Pharmacother. 2013;4(2):91.94.
• Carlson JE. Perils of polypharmacy: 10 steps to prudent prescribing. Geriatrics. 1996.;51(7):26-30, 35.
• Karch FE, Lasagna L. Toward the operational identification of adverse drug reactions. Clin Pharmacol Ther. 1977; 21:247—54.
• Kramer MS, Leventhal JM, Hutchinson TA, et al. An algorithm for the operational assessment of adverse drug reactions. I. Background, description, and instructions for use. JAMA. 1979; 242:623—32.
• Naranjo CA et al. A method for estimating the probability of adverse drug reactions. Clin Pharmacol Ther. 1981;30:239­245.
• Cuker A, Gimotty PA, Crowther MA, Warkentin TE. Predictive value of the 4Ts scoring system for heparin-induced thrombocytopenia: a systematic review and meta-analysis. Blood. 2012;120(20):4160-4167.
• MedWatch: The FDA Safety Information and Adverse Event Reporting Program. http://www.fda.gov/Safety/MedWatch/.
• CDC Vaccine Adverse Event Reporting System. https://vaers.hhs.gov/index.