Adverse drug reaction is defined by the World Health Organization (WHO) as “one which is noxious and unintended, and which occurs at doses normally used in man for the prophylaxis, diagnosis, or therapy of disease, or for the modification of physiological function.”
TYPES OF ADVERSE DRUG REACTIONS
- Type A: Type A reactions are extensions of the drug’s known pharmacology and are responsible for the majority of ADRs. Type A reactions are usually dose dependent and predictable but can be the result of concomitant disease states, drug–drug interactions, or drug–food interactions.
- Type B reactions include idiosyncratic reactions, immunological or allergic reactions, and carcinogenic/ teratogenic reactions. Type B reactions are usually not the result of a known pharmacology of the drug but seem to be a function of patient susceptibility. They are rarely predictable, are usually not dose dependent, and seem to concentrate in certain body systems such as the liver, blood, skin, kidney, and nervous system.
Pharmacists as well as all health care professionals should take an active role in monitoring, reporting, and trending ADR information. Some of the activities involved in a concurrent and ongoing ADR surveillance program at an institutional level include the following components:
- Pharmacy departments should take the lead in the collection of information and should submit all reviews and reports to the pharmacy and therapeutics committees for review and evaluation.
- Encourage all health care professionals to be involved in reporting.
- Monitor patients who are using high-risk agents.
- Review patients who have received “antidote”-type drugs.
- Notify prescribers of suspected ADRs, and encourage thorough documentation of the description of the reaction as well as the outcome in patients’ medical records.
- Report appropriately identified ADRs to the FDA.
- Develop the use of pharmacy computer systems to track ADRs.