Adverse reactions to medication that include the following predictable and unpredictable behaviors:
- Predictable reactions: Occur as a result of the medication’s side effects, for example, drugs used to reduce runny nose could result in the child feeling sleepy, or other types of drugs may produce unwanted reactions when used alongside one another. Additionally, some predictable reactions occur due to the amount of medication being used.
- Unpredictable reactions: Includes drug allergies that occur as a result of the body’s immune system reacting to the medication or ingredients used in the drug, which stimulate the body’s chemical production to defense the drug or ingredients. The symptoms may differ from case to case.
Although drug allergies only account for a small fraction of these unwanted reactions, such symptoms are crucial because they can be potentially fatal if the person suffers from anaphylaxis.
Drug allergies can flare up any time the child receives a certain form of medication, with such reactions occurring either immediately after the drug has been administered, or a short period of time later.
* Drug allergies do not necessarily occur the first time a child is exposed to a certain form of medicine. Some symptoms may only present themselves after a few exposures to medication.

