Classes of Drug Reactions

1. Allergic Reaction - When your body reacts to an allergen, it causes an allergic reaction. Allergens that cause a reaction can come in contact with the skin, be inhaled, or be eaten. Allergens can also be used to diagnose allergies and even be injected as form of treatment.

2. Idiosyncratic Reaction - Unpredictable adverse drug reactions that do not occur in most patients, but when they do occur, they can be life-threatening.

3. Iatrogenic Reaction - Reaction caused by Doctor's errors and prescription drug related causes.