Final answer:
The priority nursing intervention when a patient reports itching and throat tightness during an antibiotic infusion is to immediately stop the infusion to prevent further exposure to the allergen.
Step-by-step explanation:
The priority nursing intervention for a patient experiencing itching and a sensation of throat tightness during a secondary infusion of a new antibiotic is to stop the infusion of the antibiotic. This reaction could indicate an allergic response, which might lead to anaphylaxis, a potentially life-threatening condition. Immediate cessation of the antibiotic reduces further exposure to the substance causing the reaction.
After stopping the infusion, the nurse should continue by assessing the airway, monitoring vital signs, assessing for additional symptoms such as rash, providing appropriate supportive medical care, and alerting the Rapid Response Team if the patient's condition escalates. Documentation of the patient's reaction and interventions should follow once the immediate threat to the patient's health is addressed.