Been taking Hydroxychloroquine (Plaquenil) almost 20 years to control my Systemic Lupus.
No problems, no side effects. Works best when taken with food, and a small chance of issues with eyes -- have your ophthalmologist to do a Field of View Test annually.
More on Plaquenil and the Eyes here, plus a simple test.
http://www.sw-eng.com/plaquenil-eyes.html