Why is it essential to verify a client's allergy history before starting antibiotics?

Verifying a client's allergy history before starting antibiotics is crucial primarily to avoid potential allergic reactions. Allergies to antibiotics can lead to severe and sometimes life-threatening situations, such as anaphylaxis, which necessitates immediate medical intervention. Understanding a patient's allergy profile enables healthcare providers to select appropriate medications while eliminating those that could trigger an adverse reaction. This proactive measure not only safeguards the patient's health but also helps in maintaining the integrity of the treatment plan.

Other options, while they may seem relevant in a broader healthcare context, do not specifically address the immediate and significant safety concern posed by allergies to medications. The costs associated with treatment, the speed of healing, and the effectiveness of the drug are all important considerations, but none prioritize patient safety as directly as the avoidance of allergic reactions does.