When you need to treat or prevent malaria but can’t use primaquine, a blood-stage antimalarial drug used to kill dormant liver parasites and prevent relapses. Also known as 8-aminoquinoline, it’s effective but risky for people with G6PD deficiency, which affects millions worldwide. That’s why doctors often turn to other antimalarials that offer similar protection without the same level of danger.
chloroquine, a long-standing antimalarial that works by interfering with the parasite’s ability to digest hemoglobin. Also known as Cq, it’s still widely used in regions where malaria hasn’t developed resistance is one of the most common alternatives. It’s cheaper, easier to get, and doesn’t require G6PD testing before use. But it won’t touch the dormant liver forms of the parasite like primaquine does — so it’s not a full replacement for radical cure. Then there’s hydroxychloroquine, a modified version of chloroquine with a slightly better safety profile and fewer side effects. Also known as HCQ, it’s often used in autoimmune conditions but still holds value in malaria prophylaxis. It’s less toxic than primaquine for many people, though it still carries risks if used long-term or in high doses. Other options include atovaquone-proguanil and doxycycline, which are taken daily during travel and work by blocking parasite growth rather than targeting dormant stages.
What’s the real difference? Primaquine is the only drug that clears the hypnozoites — the hidden, sleeping forms of Plasmodium vivax and ovale that cause relapses months later. If you’re in a region where those strains are common, skipping primaquine means you might think you’re cured, only to get sick again later. But if you have G6PD deficiency, or live where testing isn’t available, your doctor might choose a different path: using a longer course of chloroquine or atovaquone-proguanil to suppress symptoms, even if it doesn’t fully eliminate the risk of relapse. It’s a trade-off — and one that depends on your health history, location, and access to care.
Below, you’ll find real-world comparisons of these alternatives, from how they stack up in cost and side effects to what patients actually experience when switching from primaquine. Some posts dig into how doctors decide between drugs, others break down the science behind why certain alternatives work — or don’t — for specific populations. Whether you’re a traveler, a patient, or just trying to understand your options, this collection gives you clear, no-fluff insights you can actually use.
Primaquine is the only drug that prevents malaria relapses from liver parasites, but it requires G6PD testing. Learn how it compares to tafenoquine, chloroquine, and ACTs - and what to do if you can't take it.
