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If allergic asthma symptoms are constantly disrupting your daily life, even though you use control medications like inhalers, it may be time to add on a biologic.

Biologics are medications you take as a shot or IV infusion. They’re monoclonal antibodies, which are human-made blood proteins. Scientists make them using cells from living organisms. Biologics bind to parts of your immune system that are responsible for asthmatic inflammation and turn it down.

“Biologics suppress this specific targeted immune response so that the asthma can be controlled without needing a broader immunosuppressant like prednisone, which comes with many side effects,” says Purvi Parikh, MD, allergist and immunologist with Allergy & Asthma Network.

Biologics are meant to be an add-on to other types of allergic asthma treatments, not a standalone medication. 

These may include:

Immunotherapy. This therapy involves seeing an allergist for allergy shots. The shots contain very small doses of the allergen that triggers a reaction in you. Over time, your body may become less reactive to the allergen.

Allergy medications. Although they aren’t treatments for asthma itself, oral and nasal antihistamines and decongestants, as well as corticosteroid and cromolyn nasal sprays, can help ease the allergic reaction causing your asthma symptoms.

Who Should Take Biologics?

Doctors may consider you a candidate for biologic treatment for allergic asthma if you:

  • Wake up at night with symptoms
  • Use your quick-relief inhaler more than two times a week
  • Need oral or injection steroids two times a year or more
  • Visit the doctor, urgent care, or ER for asthma symptoms more than two times a year

Before prescribing a biologic, your doctor will first check to be sure you’re using your current medications correctly. They’ll ask if you’ve identified any triggers and are successfully controlling them, too. They may check to make sure another condition or medication isn’t causing your symptoms.

Biologic Options

There are currently five FDA-approved biologics for treating allergic asthma, but only one -- omalizumab (Xolair) -- is specific to allergic asthma. The other four -- benralizumab (Fasenra), dupilumab (Dupixent), mepolizumab (Nucala), and reslizumab (Cinqair) -- treat eosinophilic asthma, a type of asthma where certain white blood cells (eosinophils) build up in your lungs and cause inflammation.

Omalizumab treats asthma caused by airborne allergens such as dust mites, cockroach debris, and pollen. You get it as an injection every 2 weeks or every 4 weeks, depending on dose. Kids as young as 6 can use omalizumab.

Benefits and Risks

Parikh says the use of biologics is becoming more common, both because more people are getting asthma and more cases are severe. The pros of taking biologics typically outweigh the cons.

When you take a biologic, you may see benefits such as:

  • Fewer urgent care or emergency room visits
  • Less need for oral steroids
  • A lower dosage of controller medications
  • Fewer missed days of work or school
  • Better lung function 

Because biologics target specific asthma responses instead of whole-body systems, they tend to cause fewer side effects than oral corticosteroids.

“Overall risks are very low, but since they do suppress parts of your immune system, some may increase your risk of parasitic infections,” Parikh says. “Any injection also carries risk of an allergic reaction but that is also very rare.”

Other side effects may include:

  • Sore throat
  • Muscle or joint aches
  • Headache
  • Fatigue
  • Weakness
  • Back pain
  • Redness at the injection site

You’ll get your biologic injection in a doctor’s office. Your doctor may want you to stay for up to 2 hours after to make sure you don’t have a bad reaction.

Show Sources


American Academy of Allergy, Asthma, and Immunology: “Biologics for the Management of Severe Asthma.”

Purvi Parikh, MD, allergist/immunologist, Allergy & Asthma Network.

Mayo Clinic: “Asthma medications: Know your options.”

Cleveland Clinic: “Biologic Therapy for Severe Asthma.”