Humira is a medication prescribed to treat certain inflammatory autoimmune diseases. If you're living with one of these conditions, you and your health care team may consider Humira as part of your treatment plan. Sometimes medication is necessary, whether short-term to calm a flare or long-term to manage the disease alongside other care plan practices.
It's helpful to understand that while medications may have benefits, they also can have side effects. One of the more common questions people have is, does Humira cause weight gain?
The truth is that while some people may gain weight with Humira, it's difficult to answer this question definitively because everyone's body responds differently to medications. It's also important to note that weight gain is not the only side effect associated with Humira, and some are more serious than others.
Medications can be lifesaving, but there are also steps you can take to manage an autoimmune disease that may make it less likely you will need to take them long-term. In this article, we'll look at the side effects reported with Humira — primarily weight gain — plus what you can do to support a healthy weight and overall good health while living with an autoimmune condition.
What Is Humira?
Let's start with a quick overview of Humira and how it works in your body. Humira is the brand name for a drug called adalimumab, which is a biologic medication. A biologic medication is derived from living organisms and targets parts of the immune system responsible for inflammation. (Source)
Humira is an injectable that blocks a pro-inflammatory signaling protein called tumor necrosis factor (TNF). TNF is a normal part of your immune system that helps fight infection and heal tissue. However, experts believe it's also involved in the progression of inflammation and autoimmune diseases. (Source, Source)
Autoimmunity means your body's immune system mistakes healthy cells and tissues for foreign invaders, such as bacteria or viruses. As a result, it creates an inflammatory response in your body, leading to joint pain, fatigue, and other symptoms. Tumor necrosis factor can mistakenly trigger the immune system to attack healthy body tissue and cause inflammation, pain, swelling, and other symptoms of autoimmune disease. (Source)
Humira is designed to block TNF, which could help reduce the symptoms and progression of autoimmune diseases, but this also means it could have other effects on your body and put you at higher risk for infections and serious health concerns (more on this below).
What Autoimmune Conditions Does Humira Treat?
Humira is most often prescribed for the following health conditions:
- rheumatoid arthritis
- psoriatic arthritis
- juvenile idiopathic arthritis
- ankylosing spondylitis
- plaque psoriasis
- Crohn's disease
- ulcerative colitis
- hidradenitis suppurativa
(Source)
Does Humira Cause Weight Gain?
Weight gain was not listed as a side effect in the original clinical trials examining Humira. Still, research has found that taking anti-TNF medications such as Humira can cause weight gain for some people. (Source)
For example, a study examining people taking TNF-suppressing medication found that around 13% of patients experienced weight gain, with an average increase of just over 12 lb. A recent systematic review and meta-analysis also reported a link between TNF inhibitors and weight gain. (Source, Source)
A systematic review examining children and adults with irritable bowel disease found a link between increased body weight and anti-TNF medications. A retrospective study that followed 168 people with rheumatoid arthritis taking TNF-suppressing drugs also found that more than 60% of the participants gained weight after 2 years. (Source, Source)
Does Everyone Gain Weight on Humira?
It's important to note that not everyone gains weight on Humira. While some people may gain weight as a side effect of taking Humira, others may not. Some studies show no weight changes among participants, while others suggest gender or disease severity could play a role. (Source)
It's also important to note that some of these studies included other types of anti-TNF drugs and not Humira specifically. These are also not randomized control studies, so researchers can't conclusively prove a causal relationship between Humira and weight gain.
Still, the results are worth paying attention to, as knowing that weight gain is a possible side effect of Humira can help you understand how the medication may affect you.
Why Might Humira Cause Weight Gain?
There are several reasons why Humira could cause weight gain. First, there’s some indication that biologics could impact appetite. In other words, your brain tells your body to eat more, so you take in more calories than you need. (Source, Source)
Another reason why Humira may lead to weight gain isn't directly related to the side effect of the drug itself but rather how it affects your quality of life. Sometimes pain or discomfort from autoimmune diseases can interfere with your appetite and lead to weight loss. If symptoms improve with Humira, you may start eating more and gain the weight back. Certain autoimmune conditions can also cause nutrient malabsorption. If the inflammation goes down, the body may be able to absorb nutrients again.
Interestingly, some studies show that high levels of TNF can adversely impact appetite and cause weight loss, although more research is needed to understand why. Suppressing TNF can help appetite return, so weight gain isn't necessarily a negative side effect in this case, but a good sign that appetite and overall quality of life are returning to normal. Starting at a lower weight or BMI may also be linked to more significant weight gain. (Source)
What Are Some Other Side Effects of Humira?
Humira is widely prescribed, but side effects range from mild to severe. The list is long, but here are some of the most common side effects:
- bloating
- diarrhea
- nausea
- stomach pain or cramps
- constipation
- headache
- chest pain
- fatigue
- rash
- injection site reactions (redness, itchiness, swelling)
- hair loss
(Source)