Overview

Adverse Drug Reactions

Defining ADRs

• The definition of an ADR is often confused with an adverse drug event (ADE).
• The World Health Organization (WHO) defines an ADE as “any untoward medical occurrence that may present during treatment with a pharmaceutical product.
• However, to determine which does not necessarily have a causal relationship with this treatment” (WHO 2005).
• The WHO defines an ADR as “a response to a drug which is noxious and unintended.
• This is additionally occurs at doses normally used in man for prophylaxis, diagnosis, or therapy of disease.
• An ADR is a type of ADE whose cause can be directly attributed to a drug and its physiologic properties.
• The main difference between ADRs and ADEs is that ADRs occur despite appropriate prescribing and dosing.

Why Adverse Drug Reactions Handbook ?

• Adverse Drug Reactions Handbooks, for Healthcare Professionals assists them by providing key information on potential adverse effects
• In contrast, ADEs may also be associated with inappropriate drug use or other confounders that arise during drug therapy.
• However, they are not necessarily caused by the pharmacology of the drug itself.
• A causal relationship is suspected of an ADR but is not required for an ADE.
• Adverse drug events may also be caused by medication errors.
• The National Coordinating Council defines the Medication Error Reporting and Prevention (NCC MERP) as “any preventable event that may cause or lead to inappropriate medication use or patient harm while the medication is in the control of the health care professional, patient, or consumer.” 

Classification of Adverse Drug Reactions 

• Dose-related (Augmented)
• Non–dose-related (Bizarre)
• Dose-related and time-related (Chronic)
• Withdrawal (End of use)
• Unexpected failure of therapy (Failure)

Conclusion

• As medication experts, pharmacists are a vital part of the treatment team pharmacists are a critical part of the treatment team.
• Treating an ADR consists mainly of supportive therapy with symptom management.
• Furthermore, additional steps should be taken to determine the cause of the patient’s symptoms and whether they can be attributed to drug use.
• Begin by evaluating the nature of the event.
• Thoroughly review the medical history available in the patient’s chart.
• Identify and document the clinical reaction, including the patient’s subjective report of symptoms.
• Review the patient’s medication list, and then use references such as product inserts, MedWatch reports, and published literature to evaluate whether the reaction is known to occur with any of the drugs the patient has taken.
• Classify the severity of the reaction.
• A severe reaction is fatal or life-threatening; the drug should be discontinued and not rechallenged.
• A moderate reaction requires an antidote, a medical procedure, or hospitalisation.
• In many cases, this may mean discontinuing the drug.

Book’s Pages: 45 

Related Readings:

• List of Medication with Black Box Warning
• FADIC Drug Information Flash Cards
• FADIC Clinical Pharmacology Cards Quick Guide
• Therapeutic Drug Monitoring List
• FADIC IV Fluids Book