Table of Contents
What Are Adverse Drug Reactions?
ADR definition in simple terms
Type A ADRs are predictable and dose-dependent, such as nausea from chemotherapy. Type B ADRs are unpredictable and not dose-dependent, like an allergic reaction to a medication. Subcategories for Type A include side effects, while Type B includes idiosyncratic reactions. Type A reactions are more common and can often be managed by adjusting the dosage.
Type C reactions, also known as ‘continuing’ reactions, can last for an extended period of time. These reactions may occur with certain medications, like bisphosphonates causing osteonecrosis of the jaw. Transitioning to Type D reactions, these ‘delayed’ reactions may not show up until sometime after taking a medication.
Type E reactions, which are ‘end of use’ reactions, are uncommon and occur shortly after stopping a medication. These reactions can catch patients and healthcare providers off guard, as they may not expect symptoms to arise after discontinuing a drug.
ADR vs side effect
ADR vs adverse event
Serious vs non-serious ADR
| ADR (Adverse Drug Reaction) | Side Effect | Adverse Event (AE) |
|---|---|---|
|
Harmful, unintended reaction linked to a medicine at normal use |
Unintended effect that can be expected or known |
Any medical issue after dosing, with unclear cause |
|
Requires a reasonable causal link to the drug |
May occur without harm, yet still affects comfort |
Does not require proof of drug causality |
|
Often triggers reporting, especially if serious or unexpected |
Report as an AE first, then assess causality |
QA, QC, RA, production professionals |
|
Example: hives 2 hours after antibiotic dose |
Single online GMP course with certificate |
Example: headache after dosing, cause unknown |
Quick examples of common ADRs
Why Adverse Drug Reactions Happen
What to Do If You Suspect an ADR
Final words
References
An ADR causes harm. A side effect can be expected and mild, but it may still bother patients.
Serious ADRs involve major outcomes like hospitalization, life-threatening signs, disability, or death. You should escalate these fast.
Record 4 basics: patient, reporter, suspect drug, and reaction. Then add dose, dates, outcome, and other medicines.
Ershad Moradi
Ershad Moradi, a Content Marketing Specialist at Zamann Pharma Support, brings 6 years of experience in the pharmaceutical industry. Specializing in pharmaceutical and medical technologies, Ershad is currently focused on expanding his knowledge in marketing and improving communication in the field. Outside of work, Ershad enjoys reading and attending industry related networks to stay up-to-date on the latest advancements. With a passion for continuous learning and growth, Ershad is always looking for new opportunities to enhance his skills and contribute to pharmaceutical industry. Connect with Ershad on Facebook for more information.
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