Most people are able to take chloroquine phosphate (Aralen®) without any problems. However, some people do experience side effects during treatment. Commonly reported reactions include nausea, stomach cramps, diarrhea, and vomiting. Serious problems, while not as common, are also a possibility. For example, if you develop vision problems, hallucinations, or a rash while taking chloroquine, tell your healthcare provider right away.
(To learn more about possible reactions to this drug, click Side Effects of Chloroquine. You can also click any of the links in the box to the right for specific information.)