Acute conjunctivitis: Think of it as the common cold of the eye. And just like the common cold, conjunctivitis in adults is almost always of a viral etiology. (However, in children, it is usually bacterial.)
Avoid the temptation to clamor for antibiotics because your doctors know that the anti-bacterial have no effect on the virus. True, there is a chance of a secondary bacterial super-infection, but the likelihood is quite low. To make matters worse, often the antibiotic treatment is worse than the disease itself.
Be aware that it may take 10-14 days for the infection to run its course and that the other eye may become involved. Conjunctivitis is contagious, and it is important to maintain good hygiene with hand washing to prevent its transmission through handshaking and shared surfaces such as doorknobs, towels, and faucets.