I am taking plaquenil (hydroxychloroquine) and am wondering what are side effects?

Usually none! Studies at the cleveland clinic and albany medical college clearly demonstrate that ocular toxicity with ho-q is based solely on getting more the recommended 6mg/kg of body weight. I have never seen ocular toxicity in 1000's of patient I have treated. The most common complaint is queasiness of the stomach when starting it. There are other side-effects, but i've never seen them.