Wixela Inhub is the FDA-approved generic version of Advair Diskus. It contains the same two active ingredients in the same doses, uses the same inactive ingredient (lactose monohydrate), and has been shown to deliver equivalent amounts of medication to your lungs. For most people, switching between the two should produce the same therapeutic effect.
Same Ingredients, Same Strengths
Both Wixela Inhub and Advair Diskus combine two medications: fluticasone propionate, a steroid that reduces airway inflammation, and salmeterol, a long-acting bronchodilator that keeps airways open. The formulations are identical, not just similar. Both products use micronized crystalline forms of each drug blended into lactose monohydrate powder, and they match each other in both the type and amount of every ingredient.
Both are available in three strengths:
- 100/50: 100 mcg fluticasone and 50 mcg salmeterol per dose
- 250/50: 250 mcg fluticasone and 50 mcg salmeterol per dose
- 500/50: 500 mcg fluticasone and 50 mcg salmeterol per dose
Each device holds 60 doses. The conditions they treat are the same: asthma that isn’t controlled by an anti-inflammatory inhaler alone, and COPD in people at high risk for flare-ups.
How Bioequivalence Was Established
For a generic inhaler to win FDA approval, it has to clear a higher bar than a generic pill. Pills dissolve in your stomach, so matching blood levels is relatively straightforward. Inhalers have to deliver the right amount of drug to the right part of your lungs, which depends on particle size, powder consistency, and airflow through the device.
Wixela was tested in clinical studies on adults with asthma, measuring how much of each drug reached the bloodstream after inhalation. At every strength, the amount absorbed fell within the FDA’s required window for bioequivalence (between 80% and 125% of what Advair Diskus delivered). Lab testing confirmed that the particle sizes and dose consistency matched across all strengths and airflow rates. In short, both the real-world clinical data and the bench testing confirmed that the two inhalers perform the same way.
Side Effects Are the Same
Because the formulation is identical, the side effect profile carries over directly. The most common reactions in asthma patients include upper respiratory infections, sore throat, hoarseness, oral thrush (a yeast infection in the mouth), bronchitis, cough, headaches, and nausea. For COPD patients, the list is similar but also includes pneumonia, throat irritation, viral respiratory infections, and musculoskeletal pain.
Rinsing your mouth after each use helps prevent oral thrush, just as it does with Advair. One allergy consideration applies equally to both: the lactose carrier contains trace milk proteins, so anyone with a severe milk protein allergy should not use either inhaler.
The Device Looks Different
The most noticeable difference is the inhaler itself. Advair uses the Diskus, a round, flat device where you slide a lever to load each dose. Wixela uses the Inhub, which has a slightly different shape and mechanism. Both are dry powder inhalers, meaning you don’t press a canister and time your breath. You simply open the device, load a dose, and inhale steadily through the mouthpiece. If you’re switching from one to the other, take a moment to read the instructions for the new device so the loading and inhalation steps feel familiar.
Cost Differences
Price is the main practical reason Wixela exists. Before generic competition, a monthly supply of moderate-strength Advair Diskus carried a list price around $394. GSK eventually cut that by 50%, bringing it to roughly $196, but the generic still tends to cost less at the pharmacy counter. Your actual out-of-pocket price depends on your insurance plan’s formulary. Some plans now prefer the generic and place it on a lower copay tier, while others may cover both at similar rates. If cost matters, ask your pharmacist to compare what your plan charges for each.
A 2025 analysis in Health Affairs found that the brand-name price reductions in 2024 actually drove more patients toward generics like Wixela, likely because the price cuts drew attention to the category and pharmacies increasingly stocked the cheaper option.
Can Your Pharmacist Switch You Automatically?
Wixela was approved through the abbreviated new drug application pathway, which is the FDA’s process for generics that are therapeutically equivalent to a brand-name drug. In most states, this means a pharmacist can substitute Wixela for an Advair Diskus prescription without calling your doctor, unless the prescription specifically says “dispense as written.” If you pick up your refill and notice a different-looking inhaler, this is likely what happened. The medication inside is the same.