What Lupus Medication Makes You Lose Weight? A Pharmacological Review

October 8, 2025 •

4 min read

A study found that 56% of lupus patients developed cachexia (involuntary weight loss) within five years of cohort entry [1.10.2]. While the disease itself can cause weight changes, the central question for many is: what lupus medication makes you lose weight?

Quick Summary

While weight gain is a more common side effect of primary lupus drugs like corticosteroids, some medications can indirectly lead to weight loss through side effects like nausea or loss of appetite. Unintended weight loss can also be a symptom of lupus itself.

Key Points

Weight Gain is More Common: Most primary lupus medications, especially corticosteroids like prednisone, are strongly associated with weight gain, not loss [1.8.1].
Indirect Weight Loss: Medications like hydroxychloroquine, methotrexate, and azathioprine can cause weight loss, but it's usually an indirect result of side effects like nausea or loss of appetite [1.2.1, 1.2.2, 1.5.5].
Biologics are Weight-Neutral: Newer biologic drugs such as Belimumab (Benlysta) and Anifrolumab (Saphnelo) are generally not associated with significant weight changes [1.6.4, 1.7.3].
Lupus Itself Causes Weight Loss: Unintended weight loss (cachexia) can be a direct symptom of active lupus disease, affecting over half of patients in one study [1.10.1, 1.10.2].
Steroids are the Main Culprit for Gain: Corticosteroids increase appetite, cause fluid retention, and alter fat distribution, making them the primary cause of medication-induced weight gain in lupus patients [1.3.1, 1.8.4].
Management is Key: Patients should never stop medication due to weight changes but should work with their doctor to manage side effects through diet, exercise, and possible treatment adjustments [1.9.2, 1.9.4].
Consult a Doctor: Any significant or unintentional weight change, whether gain or loss, should be discussed with a healthcare provider to determine the cause and appropriate course of action [1.2.3].

The Complex Link Between Lupus, Medication, and Weight

Living with lupus often involves managing a wide array of symptoms and treatment side effects, with weight fluctuation being a significant concern for many patients [1.9.4]. While the disease itself can cause unintentional weight loss, a condition known as cachexia, many of the frontline treatments have the opposite effect [1.10.1, 1.10.3]. The primary drivers of weight gain in lupus treatment are corticosteroids like prednisone, which can increase appetite and cause fluid retention [1.3.1, 1.8.1]. In studies, up to half of all people living with lupus were diagnosed with obesity [1.3.4].

However, the query of 'what lupus medication makes you lose weight' points to a less common but still relevant aspect of lupus pharmacology. Weight loss associated with lupus medication is often not a direct effect of the drug on metabolism but rather an indirect consequence of other side effects [1.2.1].

Medications Indirectly Associated With Weight Loss

Several medications used to treat lupus may lead to weight loss, primarily through gastrointestinal side effects.

Hydroxychloroquine (Plaquenil): Loss of appetite is a possible side effect of hydroxychloroquine [1.2.2, 1.4.2]. Other gastrointestinal issues like nausea, vomiting, diarrhea, and stomach cramps can also make eating challenging, potentially leading to weight loss [1.2.2, 1.4.4]. However, it's important to note that weight gain is not a reported side effect, making weight loss or stabilization more likely [1.4.2].
Azathioprine (Imuran): While weight loss is not a common or primary side effect, azathioprine can cause diarrhea, nausea, and vomiting, which may indirectly affect weight [1.2.1]. Some patients report losing weight gained from previous steroid treatments after starting azathioprine [1.2.1]. The drug works by suppressing the immune system and does not directly impact body weight, but by controlling lupus symptoms, it may help stabilize weight in the long run [1.2.1].
Methotrexate (Trexall): Methotrexate is an immunosuppressant that can cause side effects like nausea, loss of appetite, and mouth sores, which can contribute to weight loss [1.5.4, 1.5.5]. Studies comparing it to other arthritis drugs showed that while prednisone was associated with significant weight gain, methotrexate's effect was more modest and sometimes resulted in weight loss, particularly compared to certain other therapies [1.5.1, 1.5.3].
Mycophenolate Mofetil (CellCept): This medication is known to cause gastrointestinal side effects like diarrhea, nausea, and vomiting [1.11.2]. These issues, along with a potential loss of appetite, can lead to weight loss [1.11.3]. In clinical trials for mycophenolate, both weight loss and weight gain were observed, though neither was a majority outcome [1.11.2].

Medications Unlikely to Cause Significant Weight Changes

Newer biologic drugs used for lupus generally have a neutral effect on weight.

Belimumab (Benlysta): Weight changes, either gain or loss, were not reported as side effects in the primary clinical trials for Benlysta [1.6.1, 1.6.4]. While a post-market study noted weight gain in a very small percentage of users, it is not considered a common side effect [1.6.3].
Anifrolumab (Saphnelo): Clinical trials for Saphnelo have not indicated any significant side effects related to weight gain or loss [1.7.2, 1.7.3]. One of its key benefits is its potential to reduce the need for corticosteroids, thereby helping patients avoid steroid-induced weight gain [1.7.3].

Comparison of Lupus Medications and Their Impact on Weight


Medication	Primary Role	Common Impact on Weight	Mechanism of Weight Change
Corticosteroids	Anti-inflammatory	Weight Gain [1.3.1]	Increased appetite, fluid retention, and changes in fat storage [1.8.1, 1.8.4].
Hydroxychloroquine	Antimalarial	Weight Loss or Neutral [1.4.2]	Loss of appetite, nausea, and other gastrointestinal side effects [1.2.2].
Methotrexate	Immunosuppressant	Variable (Modest Gain or Loss) [1.5.1]	Nausea, loss of appetite, and mouth sores can lead to weight loss [1.5.5].
Azathioprine	Immunosuppressant	Variable (often neutral, sometimes loss) [1.2.1]	Gastrointestinal side effects like nausea and diarrhea [1.2.1].
Mycophenolate	Immunosuppressant	Variable (Loss or Gain) [1.11.2]	Diarrhea, nausea, and loss of appetite may cause weight loss [1.11.2]. Swelling can cause weight gain.
Belimumab (Benlysta)	Biologic (Monoclonal Antibody)	Neutral [1.6.1]	Not associated with weight changes in clinical trials [1.6.4].
Anifrolumab (Saphnelo)	Biologic (Monoclonal Antibody)	Neutral [1.7.2]	Not associated with weight changes; may reduce steroid use, preventing weight gain [1.7.3].

Managing Weight Changes on Lupus Medication

Managing weight with lupus requires a multi-faceted approach. It is crucial never to stop or alter medication dosages without consulting a doctor [1.2.5]. Open communication with your healthcare provider is key to managing side effects.

Lifestyle strategies include:

Dietary Adjustments: Focus on an anti-inflammatory diet rich in fruits, vegetables, lean proteins, and whole grains while limiting processed foods, sugar, and sodium [1.9.1, 1.9.3]. A low glycemic index diet has shown promise for weight loss in patients on corticosteroids [1.3.3].
Regular Physical Activity: Low-impact exercises like walking, swimming, or yoga can help manage weight, improve joint health, and reduce fatigue [1.9.2, 1.9.3].
Symptom Tracking: Keeping a journal of your meals, symptoms, and energy levels can help you and your doctor identify patterns and adjust your treatment plan if necessary [1.9.1].

Conclusion

While the question of 'what lupus medication makes you lose weight' is valid, the reality is that weight gain is a far more prevalent side effect, primarily due to corticosteroid use [1.8.1]. Medications like hydroxychloroquine, methotrexate, and azathioprine may lead to weight loss, but this is typically an indirect result of gastrointestinal side effects rather than a direct metabolic effect [1.2.1, 1.2.2, 1.5.5]. Newer biologics like Benlysta and Saphnelo are generally weight-neutral and offer the added benefit of potentially reducing the need for steroids [1.6.4, 1.7.3]. Ultimately, managing weight with lupus involves a collaborative effort between the patient and their healthcare team, focusing on a balanced treatment plan and healthy lifestyle choices to mitigate unwanted side effects [1.9.4].

Authoritative Link: For more information on medications used to treat lupus, visit the Lupus Foundation of America [1.3.2].

Frequently Asked Questions

No lupus medications are prescribed for the purpose of weight loss. Some, like hydroxychloroquine or methotrexate, may have side effects such as loss of appetite or nausea that can lead to unintentional weight loss [1.2.2, 1.5.5].

It is much more common to gain weight, primarily due to the frequent use of corticosteroids like prednisone, which increase appetite and cause fluid retention [1.3.1, 1.8.1].

Prednisone, a corticosteroid, increases appetite, leads to fluid retention, and can change how the body stores fat, often causing it to accumulate in the face, neck, and abdomen [1.8.4].

Yes, active lupus can cause unintentional weight loss, a condition called cachexia [1.10.1]. This can be due to a loss of appetite or the body using up energy stores to fight the inflammation from the disease [1.10.3].

Generally, no. Clinical trials for Belimumab (Benlysta) and Anifrolumab (Saphnelo) have shown that they are not associated with significant weight gain or loss [1.6.4, 1.7.3]. They can also help reduce the need for steroids, which helps prevent weight gain [1.7.3].

Hydroxychloroquine (Plaquenil) is known to have loss of appetite as a possible side effect, along with other gastrointestinal issues that can affect eating [1.2.2, 1.4.2]. Methotrexate and mycophenolate can also cause a loss of appetite [1.5.5, 1.11.3].

You should talk to your doctor. Unintentional weight loss can be a sign of medication side effects, active lupus disease, or other health issues [1.2.1, 1.10.3]. Do not stop taking your medication without medical advice.