Humira and Your Immune System: The Risk of Infection
Humira (adalimumab) is a powerful biologic medication used to treat various inflammatory conditions like rheumatoid arthritis, Crohn's disease, and psoriasis. It works by blocking Tumor Necrosis Factor-alpha (TNF-alpha), a protein that promotes inflammation [1.2.2]. By suppressing this part of your immune system, Humira reduces disease symptoms, but it also lowers your body's ability to fight off pathogens [1.2.4].
This immunosuppressive effect means you are more likely to get infections, or an existing infection could become more severe [1.2.1]. While common side effects include minor upper respiratory infections (like a cold or sinus infection), there is a risk of developing serious infections that could lead to hospitalization or, in rare cases, death [1.5.1, 1.5.4, 1.5.3]. These can include tuberculosis (TB), invasive fungal infections, and other bacterial or viral infections [1.6.3]. Because of this risk, doctors test for latent TB before starting Humira and monitor patients closely during treatment [1.6.2].
First Steps: What to Do When You Feel Sick
If you are on Humira and develop any sign of an infection, the most critical step is to contact your doctor right away [1.2.1]. Do not wait for symptoms to worsen. Signs of a possible infection include:
- Fever, sweats, or chills [1.4.3]
- Persistent cough or shortness of breath [1.4.3]
- Muscle aches or feeling very tired [1.4.3]
- Sore throat
- Diarrhea or stomach pain [1.4.3]
- Skin sores, warmth, redness, or pain on your body [1.4.3]
- Burning sensation during urination [1.4.3]
- Dental or gum problems [1.2.3]
Even a common cold is considered an infection, and your healthcare provider should be notified [1.4.1]. You should never decide to stop taking Humira on your own [1.4.3]. Your doctor will assess the type and severity of your illness to create a treatment plan and advise whether you should delay your next dose [1.4.1].
Distinguishing Minor vs. Serious Illness
Deciding if an illness is minor or serious can be difficult, which is why medical advice is essential. Generally, a minor illness might be a common cold with mild symptoms. A serious infection often makes you feel very unwell, may include a high fever, and might require you to stay in bed [1.4.6]. Your doctor will determine the severity and the appropriate course of action [1.4.1]. For a serious infection, your doctor will likely have you stop taking Humira until the infection has cleared [1.4.1].
Comparison: Managing Different Types of Illness
| Symptom Profile | Common Illness | Recommended Action for Humira Users |
|---|---|---|
| Runny nose, sneezing, mild cough, no or low-grade fever. | Common Cold | Contact your doctor before your next dose. They will advise if you should delay the injection. Many patients with mild colds may be cleared to continue treatment [1.4.1, 1.4.2]. |
| High fever, body aches, chills, significant fatigue, cough. | Influenza (Flu) | Contact your doctor immediately. You will likely be told to stop Humira and may be prescribed antiviral medication. Restarting Humira only happens after the infection resolves per your doctor's guidance [1.4.1]. |
| High persistent fever, shortness of breath, chest pain, confusion, severe headache, a skin sore that doesn't heal. | Potentially Serious Infection (e.g., Pneumonia, Sepsis, Fungal Infection) | Seek immediate medical attention. Humira must be discontinued during a serious infection or sepsis [1.6.2]. Treatment for the specific pathogen is required. |
Temporarily Stopping and Restarting Humira
The decision to stop and restart Humira is managed exclusively by your healthcare provider [1.4.1]. If you are advised to skip a dose due to illness, your doctor will tell you when it is safe to resume treatment. This is typically after the infection has fully resolved [1.7.1].
Depending on the length of the break, your doctor will decide on the appropriate restarting dose. For a short interruption, you might resume your normal maintenance dose [1.9.2]. However, for a longer pause (e.g., three months or more), your doctor might recommend repeating the initial, higher loading doses to re-establish the medication's effectiveness in your system [1.9.1, 1.9.2]. Restarting a biologic medication can sometimes lead to reduced effectiveness, so close monitoring is necessary [1.9.3, 1.9.4].
Preventative Measures and Vaccinations
While on Humira, proactive steps can help reduce your risk of infection:
- Practice Good Hygiene: Wash your hands frequently and thoroughly [1.2.2].
- Avoid Sick People: Stay away from individuals you know have contagious infections [1.4.6].
- Stay Up-to-Date on Vaccinations: Before starting Humira, it's recommended to get all necessary vaccines [1.6.1]. While on Humira, you can and should receive inactivated vaccines, like the standard flu shot and COVID-19 vaccines [1.2.4, 1.8.5].
- Avoid Live Vaccines: You should not receive live vaccines while on Humira. These contain a weakened form of the virus and can cause a serious infection in an immunocompromised person [1.8.4]. Examples include the measles, mumps, and rubella (MMR), chickenpox, and nasal spray flu vaccines [1.2.4, 1.8.2].
Conclusion: Your Doctor Is Your Partner
Living with an autoimmune disease often requires powerful medications like Humira. While the risk of infection is a significant consideration, it can be managed safely through a strong partnership with your healthcare provider. The cardinal rule is clear: at the first sign of sickness, no matter how minor it seems, communicate with your doctor. This proactive approach ensures that any potential infection is handled quickly and effectively, allowing you to continue managing your underlying condition with confidence.
For more detailed safety information, you can review the FDA's official prescribing information for Humira. https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/125057s415lbl.pdf [1.6.2]
