Hydroxychloroquine — what it is and who it helps

Hydroxychloroquine (often called HCQ) is a medication used mainly for malaria prevention and for autoimmune conditions such as lupus and rheumatoid arthritis. It calms inflammation and alters immune activity, which is why doctors prescribe it for chronic immune problems. You may have heard about HCQ in the news — clinical trials for COVID-19 did not show clear benefit and raised safety concerns, so don’t use it for that unless a physician directs you.

Common doses and how people take it

Typical dosing depends on the condition. For autoimmune diseases doctors usually prescribe 200–400 mg per day. For malaria prevention, a common schedule is 400 mg once weekly starting before travel and continuing after returning, but malaria strains and local guidance vary, so follow travel clinic advice. Never adjust dose on your own — the right dose depends on your weight, kidney function, and other medicines.

HCQ builds up in the body over weeks. That’s good for long-term control but means benefits and some side effects can take time to appear. If a doctor starts you on HCQ for lupus or RA, they often ask you to return after a few months to check how you’re doing.

Safety, side effects, and interactions

Short-term side effects can include stomach upset, headache, and sleep changes. The more serious risks show up with long-term use: eye damage (retinopathy), muscle weakness, and rare heart effects. Retinal toxicity is the big one — doctors recommend a baseline eye exam within the first year and regular screenings after that, especially if you take HCQ for years.

HCQ can affect the heart’s rhythm (it may prolong the QT interval). That risk increases if you take other QT-prolonging drugs like certain antidepressants, macrolide antibiotics (for example, azithromycin), or some antiarrhythmics. Tell your doctor about every prescription and over-the-counter drug you take. If you have a history of heart disease, an ECG may be needed before and during treatment.

Kidney and liver problems change how the drug behaves, so doctors may lower the dose. Pregnancy and breastfeeding are special cases — many specialists consider HCQ safe in pregnancy for autoimmune disease, but discuss this with your obstetrician.

Buying and using HCQ safely: always get a prescription. Use a licensed pharmacy, check packaging and expiry dates, and keep a record of the lot number if possible. Avoid unverified online sellers that don’t require a prescription. If cost or access is a problem, ask your clinician about patient assistance programs or generic options.

If you notice vision changes, new muscle weakness, unexplained heart symptoms (fast/irregular heartbeat, fainting), or serious allergic reactions, stop the medicine and contact your provider right away. For ongoing treatment, stick with scheduled eye checks and regular follow-ups so HCQ can help safely over the long run.