When to Stop Hydroxychloroquine Before Surgery?

Hydroxychloroquine generally does not need to be stopped before surgery. Unlike many other disease-modifying antirheumatic drugs, which surgeons and rheumatologists often pause in the days or weeks leading up to a procedure, hydroxychloroquine (commonly known by the brand name Plaquenil) carries a favorable enough safety profile that most guidelines recommend continuing it straight through the perioperative period. The reasoning behind this advice touches on infection risk, disease flare prevention, blood-clot protection, and some cardiac considerations worth discussing with your anesthesia team.

What the Guidelines Actually Say

The American College of Rheumatology (ACR) and the American Association of Hip and Knee Surgeons (AAHKS) jointly published perioperative management guidelines specifically addressing patients on antirheumatic medications who are heading into elective surgery. For hydroxychloroquine, the recommendation is straightforward: continue the drug through surgery, including on the day of the procedure. This stands in contrast to biologic agents and certain other immunosuppressants, which the same guidelines recommend withholding for a dosing cycle or longer before an operation.

The reason hydroxychloroquine gets this green light is that the available evidence consistently fails to link it to the surgical complications that worry clinicians most, particularly wound infections and delayed healing. A review of antirheumatic treatments in surgical patients found that data on hydroxychloroquine do not show increased risks of infection.¹ An analysis of over 700 foot and ankle procedures in patients with rheumatoid arthritis examined hydroxychloroquine alongside other agents and similarly failed to find a statistical association with either healing complications or postoperative infections.²

Why Hydroxychloroquine Is Different from Other DMARDs

If you take methotrexate, a biologic like adalimumab, or a targeted synthetic drug like tofacitinib, your surgical team will almost certainly ask you to pause it before the operation. Those drugs suppress the immune system in ways that can interfere with wound healing and raise infection risk in the vulnerable postoperative window. Hydroxychloroquine works differently. It modulates the immune system rather than suppressing it in the heavy-handed way that many other DMARDs do. Its mechanism involves altering how certain immune cells process signals rather than broadly shutting down immune activity, which is why it has long been considered one of the milder agents in the rheumatology toolbox.

This distinction matters practically. Hydroxychloroquine also has an exceptionally long half-life, on the order of 40 to 50 days. Even if you stopped taking it weeks before surgery, meaningful amounts of the drug would still be circulating in your tissues. Stopping it a few days or even a couple of weeks before an operation would accomplish very little pharmacologically but could allow your underlying disease to become more active. For a drug that does not appear to raise surgical risk in the first place and that would linger in your system regardless, the cost-benefit calculation clearly favors continuation.

The Risk of Stopping and Triggering a Flare

For patients with systemic lupus erythematosus or rheumatoid arthritis, hydroxychloroquine is often the backbone of their treatment regimen. Discontinuing it, even briefly, can trigger disease flares. In lupus, a flare around the time of surgery is a serious concern because it can involve the kidneys, joints, skin, or blood-forming system, all of which complicate recovery. Perioperative management reviews for lupus patients emphasize careful multidisciplinary planning that accounts for disease activity and severity, and generally favor allowing patients who are stable to continue their immunomodulating therapy through surgery.¹

In rheumatoid arthritis, a postoperative flare means swollen, painful joints at exactly the time you need to be mobilizing and participating in physical therapy. Joint replacement patients, for example, depend on early movement to achieve good outcomes. A disease flare that makes every step excruciating can derail rehabilitation. Because hydroxychloroquine does not appear to increase surgical complications, there is no upside to accepting that flare risk.

This logic applies even more strongly to patients whose disease is well controlled on hydroxychloroquine alone or in combination with other agents. Removing one pillar of a treatment strategy right before a major physiological stress is generally unwise unless the drug itself poses a clear perioperative hazard, and the evidence says hydroxychloroquine does not.

Thrombosis Protection You May Not Want to Lose

One of the less-discussed benefits of hydroxychloroquine is its effect on blood clotting, which is especially relevant around surgery. Surgery itself raises the risk of blood clots because of immobility, tissue damage, and inflammation. For patients with lupus, the risk is already elevated, particularly in those who carry antiphospholipid antibodies, a group of immune proteins that make blood clot more readily than it should.

Research in a lupus cohort found that thrombosis rates dropped by about 12% for every 200 ng/mL increase in hydroxychloroquine blood levels, and patients with the highest blood levels had roughly a 69% lower rate of thrombotic events compared to those with the lowest levels.³ Animal studies have shown that hydroxychloroquine directly counteracts the clot-promoting effects of antiphospholipid antibodies, reducing both the size of clots and the time they take to form.⁴

Stopping hydroxychloroquine before surgery means removing that antithrombotic protection at the very moment clot risk is peaking. For lupus patients, and especially for those with antiphospholipid syndrome or antiphospholipid antibodies, continuing the drug through the perioperative period is arguably protective rather than harmful. This is one more reason the recommendation is overwhelmingly to keep taking it.

QT Prolongation and What Your Anesthesiologist Should Know

Hydroxychloroquine is not completely without cardiac concerns, though these rarely change the surgical calculus. The drug can prolong the QT interval on an electrocardiogram, a measurement that reflects how long the heart’s electrical system takes to reset between beats. When the QT interval stretches too far, it can occasionally set up dangerous heart rhythms.

A study of chronic hydroxychloroquine users found that certain patients face higher risk for significant QT prolongation. Diabetes was the strongest independent predictor, raising the odds roughly ninefold, and concurrent use of other QT-prolonging medications nearly tripled the risk.⁵ Serious arrhythmias remained rare overall in that cohort, but the finding matters in the surgical context because several anesthetic drugs can also prolong the QT interval. The combination deserves attention.

Case reports have documented refractory ventricular arrhythmia associated with chronic hydroxychloroquine use, reinforcing that the cardiac risk, while small, is real.⁶ None of this means you should stop the drug before surgery. It means your anesthesiologist should know you are on it. A preoperative electrocardiogram can establish your baseline QT interval, and the anesthesia team can choose drugs that are less likely to stretch it further. Patients with diabetes, those on other QT-prolonging medications, or those with a history of heart-rhythm problems warrant extra monitoring.

The practical takeaway is communication, not discontinuation. Make sure hydroxychloroquine appears on your medication list for every preoperative visit, and flag it specifically for the anesthesia team if you have any of the additional risk factors.

Surgery Day Logistics

You will likely be told to take nothing by mouth for several hours before your procedure. Hydroxychloroquine, like most essential daily medications, can be taken with a small sip of water on the morning of surgery. Confirm this with your surgical team, but the standard approach at most centers is that long-term medications are swallowed with a minimal amount of water before the patient arrives, unless there is a specific reason not to.

If you are having same-day surgery and expect to be eating and drinking within hours, you can simply resume your normal schedule afterward. For longer procedures or hospital stays where you may not be able to swallow pills immediately, the gap is unlikely to matter because of hydroxychloroquine’s extremely long half-life. Missing a single dose, or even two or three, does not appreciably change your blood levels. This is very different from a drug like methotrexate, where timing and dosing intervals are critical.

That same long half-life has another implication for patients and clinicians to keep in mind. If your team is measuring hydroxychloroquine blood levels around the time of surgery for any reason, the timing of your last dose relative to the blood draw can affect the results. Researchers have emphasized that clinicians should always ask patients when they last took their hydroxychloroquine before interpreting a blood level, since failing to do so can lead to misclassifying whether someone has actually been taking the drug consistently.⁷

When Extra Caution Might Apply

The advice to continue hydroxychloroquine through surgery is robust for most patients undergoing most procedures. A few situations call for more careful discussion with your treatment team, though stopping the drug outright is still not typically recommended.

• Kidney impairment: Hydroxychloroquine is cleared partly through the kidneys. If you have significant kidney disease, the drug may accumulate to higher-than-expected levels. This can amplify the cardiac risks described above. Your rheumatologist may already have adjusted your dose, but it is worth flagging for the surgical team.
• Existing heart-rhythm issues: Patients who already have a prolonged QT interval, a history of arrhythmias, or who take multiple other medications known to affect the QT interval deserve a preoperative cardiology review, not necessarily to stop hydroxychloroquine but to plan anesthetic management carefully.
• Very long duration of use: Patients who have been on hydroxychloroquine for many years are typically monitored for retinal toxicity. This does not directly affect surgical planning, but it is part of the overall health picture that your care team should be aware of when coordinating your perioperative care.
• Active lupus flare at the time of surgery: If your disease is already flaring when surgery is being scheduled, the conversation shifts from “should we stop hydroxychloroquine” to “should we postpone the procedure if it is elective.” Operating during active systemic inflammation raises the stakes across the board, and continuing all of your immunomodulating therapies becomes even more important.

In none of these scenarios does the answer typically become “stop hydroxychloroquine and proceed with surgery.” The answer is more nuanced: adjust what can be adjusted, communicate what needs to be communicated, and involve the right specialists in the planning.

Common Misconceptions About Antirheumatic Drugs and Surgery

One reason this question comes up so often is that patients and sometimes clinicians conflate hydroxychloroquine with the broader category of immunosuppressive drugs. If you have been told to stop your biologic or your methotrexate before surgery, it is natural to wonder whether hydroxychloroquine should be stopped too. The answer is different because the drug is different. Lumping all rheumatic disease medications together and withholding them as a group “just to be safe” actually makes things less safe by exposing you to flare risk and removing the antithrombotic benefit, all without reducing infection or wound-healing problems.

Another misconception is that you should stop all medications before surgery unless specifically told to continue them. The reality is the reverse for chronic disease medications: you continue everything unless there is a documented reason to stop. Hydroxychloroquine, blood pressure medications, thyroid replacement, and many other daily drugs fall into this “keep taking it” category. The drugs that get paused are the exceptions, not the rule, and they are paused because specific evidence shows they interfere with surgical outcomes or anesthesia.

Finally, some patients worry that continuing hydroxychloroquine will interact with the anesthesia or pain medications they receive during and after surgery. Beyond the QT interval issue already discussed, there are no well-documented anesthetic interactions that would lead to stopping the drug. Hydroxychloroquine does not thin the blood in the way that anticoagulants do, does not affect platelet function the way aspirin does, and does not interfere with standard pain management. The drug stays, and your anesthesia team adapts their monitoring plan around it.

Hydroxychloroquine Blood Levels and Perioperative Monitoring

Measuring hydroxychloroquine blood levels has become increasingly common in rheumatology practice, mainly as a way to check whether patients are actually taking the medication consistently.⁷ In the context of surgery, blood levels are not routinely checked, but they can be informative in specific situations. For lupus patients with antiphospholipid antibodies, for instance, knowing that hydroxychloroquine blood levels are adequate provides some reassurance about thrombosis protection heading into a high-risk period.³

If levels come back unexpectedly low before a planned procedure, it could signal that a patient has not been taking the drug regularly. That finding changes the preoperative picture because a patient who has been off hydroxychloroquine for weeks or months is at higher flare risk and has lost whatever antithrombotic benefit the drug was providing. In that scenario, restarting the drug before surgery and potentially delaying the procedure until levels rebuild may be worth discussing, depending on the underlying diagnosis and urgency of the operation. The drug’s long half-life means it takes weeks for blood levels to reach a steady state after starting or restarting, so a last-minute dose the night before surgery would not meaningfully change things.