Eosinophilic Asthma — When Eosinophils Drive Your Symptoms

If your asthma keeps flaring even on daily inhalers, eosinophils — a type of white blood cell — might be the cause. Eosinophilic asthma often means more coughing, nighttime worsening, and frequent steroid bursts. The good news: once identified, there are targeted treatments that can cut attacks and lower steroid use.

How you know it’s eosinophilic

Your doctor will look for specific signs: frequent exacerbations, nasal polyps or chronic sinus problems, adult-onset symptoms, and worsening at night. Simple tests help confirm it. A blood test checks eosinophil count (doctors often flag counts above ~150–300 cells/µL). A sputum test or a FeNO breath test (high FeNO suggests airway inflammation) can add detail. If these point to eosinophilic inflammation, a specialist referral to an allergist or pulmonologist is common.

Don’t skip the basics: review your inhaler technique, check for triggers (smoke, strong smells, workplace irritants), and make sure you’re on the right inhaler dose before assuming you need advanced therapies.

Practical treatment steps

Start with what's proven: inhaled corticosteroids (ICS) reduce eosinophilic inflammation and are the backbone of care. Long-acting bronchodilators (LABA) are used with ICS to improve daily control. For repeated exacerbations or steroid dependence, biologic drugs are a game-changer. Options include anti-IL-5 medicines (mepolizumab, benralizumab, reslizumab) which lower eosinophil levels, and dupilumab which blocks IL-4/IL-13 pathways. These drugs are for people whose asthma stays uncontrolled on high-dose ICS plus additional meds, and they often reduce emergency visits and oral steroid needs.

Biologics require a prescription and specialist evaluation. Expect blood tests, a review of your exacerbation history, and sometimes trial periods to see benefit. Common practical downsides: regular injections or infusions, monitoring for side effects, and cost or insurance prior authorization.

Other useful steps: treat upper airway problems (sinusitis, nasal polyps), get flu and pneumococcal vaccines, stop smoking, and manage weight and GERD if present. Small fixes — cleaning out dust, using HEPA filters, and avoiding known workplace irritants — often pay off.

When to push for a specialist? Ask for one if you still need frequent oral steroid courses, your quality of life is poor, or you’ve had hospital admissions. A specialist will map tests, consider biologics, and design an action plan with clear steps for flare-ups.

Talk openly with your doctor about goals: fewer attacks, lower steroid use, and better daily control. If you want to be proactive, bring a record of inhaler use, any steroid courses, and recent blood tests to your appointment. That gives your care team the clearest picture to decide the best next move.