How to take Hydroxychloroquine. Take hydroxychloroquine with a meal or a glass of milk. To prevent malaria: Start taking the medicine 2 weeks before entering an area where malaria is common. Continue taking the medicine regularly during your stay and for at least 8 weeks after you leave the area.
Hydroxychloroquine interactions. Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Some products that may interact with this drug include: ampicillin, cimetidine, digoxin, penicillamine, drugs that may be harmful to your liver (e.g., high doses of acetaminophen, isoniazid).