Adverse Drug Reaction Surveillance: Practical Methods for Developing a Successful Monitoring Program

Josephine A. Vitillo, PharmD, BCPS, CGP


December 18, 2000

In This Article


An ADE is a term synonymous with drug misadventures and encompasses both medication errors and ADRs.[10]

The American Society of Health-System Pharmacists (ASHP)[11] defines an ADR as any unexpected, unintended, undesired, or excessive response to a medicine that:

  • requires discontinuing the medicine (therapeutic or diagnostic),

  • requires changing the medication therapy,

  • requires modifying the dose (except for minor dosage adjustments),

  • necessitates admission to the hospital,

  • prolongs stay in a healthcare facility,

  • necessitates supportive treatment,

  • significantly complicates diagnosis,

  • negatively affects prognosis, or

  • results in temporary or permanent harm, disability, or death.

Several other definitions of ADRs exist, including those of the World Health Organization (WHO),[12] Karch and Lasagna,[13] and the Food and Drug Administration (FDA).[14]

WHO defines an ADR as any response to a drug that is noxious and unintended, and that occurs at doses normally used in man for prophylaxis, diagnosis, or therapy of disease or for the modification of physiologic function.[12]

Similarly, Karch and Lasagna state, "any response to a drug that is noxious and unintended, and that occurs at doses used in humans for prophylaxis, diagnosis, or therapy, excluding failure to accomplish the intended purpose," is an ADR.[13]

For reporting purposes, the FDA categorizes a serious adverse event (events relating to drugs or devices) as one in which the patient outcome is death, is life-threatening (real risk of dying), hospitalization (initial or prolonged), disability (significant, persistent, or permanent), congenital anomaly, or required intervention to prevent permanent impairment or damage.[14]