Doctors often use certain medications to treat infections. A few people have a reaction to some of these medications, such as itching, swelling, or trouble breathing. This is an example of *

Allergy

Explanation:

Allergy occurs when the body system reacts to the introduction of a foreign substance. The immune system plays an important role in the elimination of substances that are capable of causing harm to the body, substances that trigger an allergic reaction in the body is known as allergen.

When an allergen is introduced into the body, the immune system views it as an intruder that is capable of destroying various tissues and cells. It therefore manufactures antibodies to fight off the intruders thereby resulting in an allergic reaction.

Medications such as antibiotics can cause allergic reactions such as itching and swelling of the skin.

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