Final answer:
The symptoms described, including hives, nasal congestion, and conjunctivitis, suggest an allergic reaction potentially caused by exposure to various allergens commonly found in an ER setting which could trigger such manifestations of hypersensitivity of the immune system.
Step-by-step explanation:
If you have started working in a busy ER and have developed hives, nasal congestion, and conjunctivitis, you are most likely experiencing an allergic reaction. These symptoms are indicative of common allergies which result from the immune system's hypersensitivity to substances in the environment that are typically harmless. People with allergies often experience symptoms like itchy, watery eyes, swollen tissues, and sneezing. Allergic rhinitis, commonly known as hay fever, is one such reaction. It is possible that the high-stress and diverse environmental factors present in an ER could expose you to allergens such as latex, medication, or a number of other triggers leading to these symptoms.
Causes for such allergic reactions include a range of factors from pollen (typical in hay fever) to certain foods like shellfish and peanuts. Other potential workplace triggers could be exposure to latex (contact dermatitis) or other substances which cause skin rashes and respiratory issues. The most severe form of an allergic reaction is anaphylaxis, which may cause life-threatening symptoms like airway blockage and dangerous drops in blood pressure, requiring immediate medical attention.