IL-17 inhibitors are a class of biologic medications used primarily to treat autoimmune conditions like psoriasis, psoriatic arthritis, and ankylosing spondylitis. The most common side effects associated with IL-17 inhibitors include headache, nasopharyngitis (inflammation of the nasal passages and pharynx), and infections.
Understanding IL-17 Inhibitor Side Effects
While generally effective for their approved indications, IL-17 inhibitors work by targeting specific proteins involved in the immune system, which can lead to various side effects. These can range from mild and common to more serious, requiring medical attention.
Common Side Effects
Many individuals experience mild side effects, especially when first starting treatment. These often resolve on their own or with minimal intervention.
Common side effects may include:
- Infections: Upper respiratory tract infections (like colds or sinus infections), nasopharyngitis, and oral candidiasis (thrush) are frequently reported.
- Headache: A common neurological side effect.
- Injection Site Reactions: Redness, pain, swelling, or itching at the injection site are typical, as these medications are administered via injection.
- Gastrointestinal Issues: Diarrhea and nausea can occur.
- Fatigue: Some patients report feeling tired or generally unwell.
Here's a quick overview of some common side effects:
| Side Effect | Description |
|---|---|
| Nasopharyngitis | Inflammation of the nose and throat, similar to a cold. |
| Headache | Pain or discomfort in the head or face. |
| Upper Respiratory Infections | Infections affecting the nose, throat, or sinuses. |
| Injection Site Reactions | Redness, pain, swelling, or itching at the injection area. |
| Diarrhea | Loose, watery stools. |
Serious Side Effects
Although less common, some side effects of IL-17 inhibitors can be serious and may require immediate medical attention. It's crucial to be aware of these potential risks and discuss them with your healthcare provider.
1. Serious Infections
Because IL-17 inhibitors modulate the immune system, there is an increased risk of developing serious infections. This includes:
- Opportunistic Infections: Infections caused by pathogens that usually don't cause disease in healthy individuals but can affect those with weakened immune systems.
- Fungal Infections: Such as candidiasis, especially oral or esophageal candidiasis.
- Bacterial Infections: Including cellulitis or pneumonia.
- Tuberculosis (TB): Although rare, reactivation of latent TB is a concern, and screening for TB is typically performed before starting treatment.
2. Inflammatory Bowel Disease (IBD)
There have been reports of new-onset or exacerbation of inflammatory bowel disease (Crohn's disease or ulcerative colitis) in patients taking IL-17 inhibitors, particularly with some agents like secukinumab. Patients with a history of IBD should discuss this risk with their doctor.
3. Hypersensitivity Reactions
Allergic reactions, ranging from mild skin rashes to severe systemic reactions like anaphylaxis, can occur. Symptoms may include:
- Hives or rash
- Swelling of the face, lips, tongue, or throat
- Difficulty breathing
- Dizziness or fainting
4. Liver Enzyme Elevations
In some cases, IL-17 inhibitors may cause elevations in liver enzymes, indicating potential liver stress. Regular monitoring of liver function tests may be recommended by your doctor.
5. Neutropenia
A decrease in the number of neutrophils (a type of white blood cell important for fighting infections) has been observed in some patients. This can increase the risk of infection.
6. Mood Changes
Rarely, psychiatric side effects, including depression or suicidal ideation, have been reported, particularly with brodalumab. Patients or their caregivers should report any new or worsening mood changes to their doctor immediately.
When to Contact Your Doctor
It's important to contact your healthcare provider if you experience any of the following while on an IL-17 inhibitor:
- Signs of serious infection (e.g., persistent fever, chills, severe cough, unexplained weight loss).
- New or worsening abdominal pain, diarrhea, or blood in stools.
- Symptoms of an allergic reaction.
- Unexplained bruising or bleeding.
- Significant mood changes, new or worsening depression, or thoughts of self-harm.
- Any side effect that is severe, persistent, or causes you concern.
Your doctor can help you manage side effects, adjust your treatment plan if necessary, or determine if the medication needs to be stopped. For comprehensive information on specific IL-17 inhibitors, consulting the official prescribing information from regulatory bodies like the FDA or reputable medical sources such as Mayo Clinic is recommended.
