When you have severe asthma that won’t respond to inhalers or steroids, mepolizumab, a targeted biologic therapy that blocks interleukin-5 (IL-5) to reduce harmful eosinophils. Also known as Nucala, it’s not a cure—but for some, it’s the difference between daily flare-ups and breathing normally. This isn’t your average asthma med. It’s an injection given once a month, designed for people whose lungs are flooded with eosinophils—white blood cells that turn harmless irritants into full-blown attacks.
Mepolizumab works by stopping IL-5, the signal that tells your body to make too many eosinophils. Fewer eosinophils mean less swelling, less mucus, and fewer trips to the ER. It’s approved for adults and kids as young as six with eosinophilic asthma, especially when blood tests show high eosinophil counts. People who’ve tried multiple inhalers and still struggle often find relief here. It’s not for everyone—your doctor will check your eosinophil levels and history before prescribing it. And while it’s expensive, many insurance plans cover it if you’ve hit the limit on standard treatments.
Related to mepolizumab are other biologic therapies, targeted drugs that calm the immune system’s overreaction in asthma like benralizumab and reslizumab. These also target IL-5 or its receptor, but each has slight differences in dosing, delivery, and who responds best. Then there’s eosinophilic asthma, a subtype of severe asthma driven by high levels of eosinophils in the airways, which makes up about 5-10% of all asthma cases. It’s often linked to nasal polyps, chronic sinus infections, and poor response to steroids. If you’ve been told your asthma is "refractory," this might be why.
You won’t find mepolizumab in a pill bottle. It’s a shot you get at the doctor’s office or sometimes at home after training. Side effects are usually mild—headache, fatigue, or sore throat—but serious reactions like allergic responses are rare. It doesn’t replace your rescue inhaler. Think of it as background control, like a silent guard keeping your airways calm between flare-ups.
Below, you’ll find real-world stories and clinical insights from people who’ve used mepolizumab, comparisons with other biologics, and practical tips for tracking your progress. Whether you’re considering this treatment, already on it, or just trying to understand why it’s different, these posts cut through the noise and give you what actually matters.
