Hydroxychloroquine: what it does, how to use it, and what to watch for

Hydroxychloroquine is a prescription medication used for malaria, lupus, and rheumatoid arthritis. It calms immune activity and can lower inflammation, so people with chronic autoimmune conditions often take it daily. You may have heard it mentioned a lot — here's a clear, practical look at when it helps, what risks to expect, and how to get it safely.

What hydroxychloroquine treats and typical doses

For autoimmune conditions like lupus or rheumatoid arthritis, common dosing is 200–400 mg per day depending on body weight and response. Doctors usually aim for the lowest effective dose to reduce long-term risks. For malaria prevention, a typical regimen is 400 mg once weekly, starting 1–2 weeks before travel and continuing during travel plus 4 weeks after. Never change your dose without talking to your prescriber — exact dosing can vary by condition, weight, and other medications.

Safety, side effects, and monitoring

Short-term side effects are usually mild: nausea, stomach upset, headache, or rash. The main long-term risk is eye damage (retinopathy) that may cause vision loss if not caught early. That's why most doctors order a baseline eye exam within the first year of starting hydroxychloroquine and regular screening after several years — sooner if your dose is high, you have kidney disease, or you take it for many years.

Another safety issue is heart rhythm changes. Hydroxychloroquine can lengthen the QT interval in some people, raising the risk of dangerous arrhythmias, especially if you take other QT-prolonging drugs (for example, certain antibiotics or antidepressants). Tell your doctor about all medicines and supplements you take. If you have heart disease, low potassium, or abnormal ECGs, your doctor may avoid it or monitor you more closely.

Blood tests and routine check-ins help catch problems early. If you notice blurred or darkened vision, new palpitations, unexplained muscle weakness, or unusual bleeding, contact your provider right away.

Want to buy hydroxychloroquine online? Get a valid prescription first. Use licensed pharmacies that require prescriptions, show contact details, and have clear return and privacy policies. Avoid sites that sell without a script or that look poorly made. Compare prices but prioritize safety over a tiny discount. If ordering internationally, check rules for importing prescription meds to your country.

Simple steps to stay safe: 1) always follow your prescriber's dose; 2) get the recommended eye exams and any ECGs your doctor suggests; 3) report new symptoms quickly; and 4) only buy from reputable pharmacies with a prescription requirement. If you’re unsure whether hydroxychloroquine is right for you, ask for a clear explanation of benefits and risks from your doctor before starting treatment.