Side Effects of Humira (Adalimumab)
Humira carries significant risks including serious infections (particularly tuberculosis reactivation), injection site reactions, and rare but serious complications including malignancies, heart failure, neurological disorders, and autoimmune syndromes that require careful monitoring and patient education. 1
Most Common Side Effects
The most frequently reported adverse effects are generally mild to moderate and include:
- Injection site reactions (redness, rash, swelling, itching, bruising) occurring in a substantial proportion of patients, typically resolving within a few days 1, 2
- Upper respiratory infections including sinus infections 1
- Headaches 1
- Gastrointestinal symptoms including nausea and upset 3
- Rash (non-injection site) 1
Serious Infectious Complications
Tuberculosis Reactivation
- TB screening is mandatory before initiating therapy with tuberculin skin testing and chest radiograph 4
- Patients may develop active TB even with negative baseline screening 1
- Monitor for persistent cough, low-grade fever, weight loss, and wasting during treatment 1
Other Serious Infections
- Two-fold increased risk of serious infections requiring hospitalization 2
- Serious infection rate of 2.03 per 100 patient-years in long-term studies 4
- Risk includes Legionella pneumophila pneumonia (cluster cases reported), Pneumocystis jirovecii pneumonia, and atypical mycobacteria 4
- Deep fungal infections (histoplasmosis, blastomycosis, coccidioidomycosis) particularly in endemic areas 4
- Contraindicated during active infections; discontinue if febrile illness develops, especially requiring antibiotics 1, 2
Hepatitis B Reactivation
- Carriers of hepatitis B virus can experience viral reactivation during treatment 1
- Hepatitis serology required before treatment initiation 4
- Monitor with blood tests before, during, and for several months after stopping therapy 1
- Warning signs include muscle aches, extreme fatigue, dark urine, jaundice, clay-colored stools, fever, and abdominal discomfort 1
Hematologic Adverse Effects
- Cytopenias including pancytopenia can occur, though relatively uncommon 3, 2
- Symptoms include persistent fever, easy bruising/bleeding, or pallor 1
- Thromboembolic events with hazard ratio of 7.6 in patients developing anti-adalimumab antibodies 3
- Risk increased with concomitant immunosuppressive medications 3
- The American Society of Clinical Oncology recommends hematology consultation for serious hematologic effects and potential treatment discontinuation 3
Cardiovascular Complications
- New onset or worsening heart failure can occur 1, 2
- Monitor for shortness of breath, sudden weight gain, and ankle/feet swelling 1
- Use extreme caution in patients with pre-existing congestive heart failure 2
Neurological Complications
- CNS demyelination is a rare but serious complication 1, 5
- Multiple sclerosis-like syndromes or other demyelinating patterns reported 2, 5
- Warning signs include numbness, tingling, vision problems, arm/leg weakness, and dizziness 1
- Consider baseline brain MRI in asymptomatic individuals before initiating therapy to exclude pre-existing demyelinating disease 5
Autoimmune Reactions
Lupus-Like Syndrome
- Reported in 15 patients with adalimumab in systematic analysis 4
- Symptoms include chest pain/discomfort, shortness of breath, joint pain, and photosensitive rash on cheeks/arms 1
- Symptoms typically improve with drug discontinuation 1
Vasculitis
- Five cases reported with adalimumab in detailed analysis 4
- Drug-specific risk documented in rheumatoid arthritis patients 4
Hepatotoxicity
- Liver problems can lead to liver failure and death 1
- Monitor for extreme fatigue, jaundice, poor appetite, vomiting, and right upper quadrant abdominal pain 1
- Elevated transaminases reported, suggesting intermittent liver function monitoring is useful 2
Dermatologic Reactions
- New-onset or worsening psoriasis paradoxically reported 1
- Manifests as red scaly patches or pus-filled raised bumps 1
- May require treatment discontinuation 1
Pulmonary Complications
- Pulmonary fibrosis as new event or exacerbation of underlying fibrosis 4
- Interstitial pneumonias reported in at least 18 patients receiving anti-TNF agents 4
- Sarcoidosis cases reported, mechanism unclear 4
- Report any shortness of breath or breathing changes immediately 4
Malignancy Risk
- Risk for malignancy with anti-TNF agents remains unclear 4
- Potential promotion of lymphoma reported as rare complication 2
Hypersensitivity Reactions
- Serious allergic reactions can occur 1
- Immediate medical attention required for hives, facial/lip/mouth swelling, or difficulty breathing 1
- Risk of hypersensitivity documented in Medicare patients with rheumatoid arthritis 4
Rare Menstrual Effects
- Menorrhagia and severe menstrual pain reported 6
- May require oral contraceptive management 6
- Symptoms resolve with drug discontinuation 6
Monitoring Requirements
Pre-treatment screening:
- Tuberculin skin testing and chest radiograph 4
- Hepatitis B serology 4
- Consider baseline brain MRI if neurological concerns 5
During treatment:
- Temperature monitoring frequently 4
- Intermittent blood counts and liver function tests 2
- Hepatitis B monitoring in carriers 1
Patient education priorities:
- Report fever, infection signs (cough, aches, wound infections, urinary symptoms, GI symptoms) immediately 4
- Avoid live vaccines during therapy 4