What are common causes of conjunctivitis?

Conjunctivitis, commonly referred to as pink eye, can arise from multiple causative factors, and understanding these helps in both diagnosis and treatment. The correct choice identifies that conjunctivitis can be caused by allergies, bacterial infections, or viral infections.

Allergic conjunctivitis occurs when the conjunctiva reacts to allergens like pollen, pet dander, or dust mites, leading to symptoms such as redness and itching. Bacterial conjunctivitis results from harmful bacteria which can infect the conjunctiva, often leading to discharge and discomfort. Viral conjunctivitis is typically caused by viruses, such as those responsible for the common cold, and is often contagious.

Since conjunctivitis can stem from these diverse origins, identifying the correct causes helps in selecting appropriate treatments. Treatments may vary significantly depending on whether the conjunctivitis is allergic, bacterial, or viral, reinforcing the importance of recognizing that there is no single cause but rather a range of potential etiologies.