Wixela Inhub Drug Interactions: What to Avoid and What to Tell Your Doctor

Wixela Inhub contains two active ingredients — fluticasone propionate and salmeterol — each of which can interact with other medications. Some interactions are serious and require your doctor to either avoid the combination or adjust doses carefully. This guide covers the most important drug interactions for Wixela Inhub patients.

The Most Critical Interaction: Other LABA Medications

Do NOT use Wixela Inhub if you are already taking another LABA medication. This includes:

• Formoterol (Symbicort, Dulera, Perforomist, Brovana)
• Arformoterol tartrate (Brovana)
• Indacaterol (Arcapta, Utibron)
• Vilanterol (Breo Ellipta, Trelegy Ellipta, Anoro Ellipta)

Using two LABA medications simultaneously increases the risk of serious cardiovascular side effects, including dangerous heart rhythm changes, and potentially fatal outcomes. This is an absolute contraindication.

Major Interaction: Strong CYP3A4 Inhibitors

Both fluticasone propionate and salmeterol are metabolized by the CYP3A4 enzyme in the liver. Drugs that strongly inhibit CYP3A4 block the breakdown of these medications — dramatically increasing their blood levels, which can cause serious side effects.

Strong CYP3A4 inhibitors to avoid with Wixela Inhub:

• Azole antifungals: Ketoconazole, itraconazole, voriconazole. Ketoconazole increased salmeterol AUC by 16-fold in clinical studies.
• HIV protease inhibitors: Ritonavir, atazanavir, indinavir, saquinavir, nelfinavir
• Cobicistat: Found in Stribild, Genvoya, Descovy (HIV medications)
• Macrolide antibiotics: Clarithromycin, telithromycin (not erythromycin — that's a moderate inhibitor)
• Nefazodone: An antidepressant

When combined with Wixela Inhub, these drugs can increase systemic fluticasone levels (raising the risk of adrenal suppression and Cushing-like effects) and increase salmeterol exposure (raising cardiovascular risk including QT prolongation).

Moderate Interaction: Beta-Blockers

Beta-blockers (used for high blood pressure, heart failure, glaucoma drops, and other conditions) can block the bronchodilating effect of salmeterol. They work on the same receptors (beta-adrenergic) but in opposite directions. Non-selective beta-blockers are particularly problematic for asthma and COPD patients as they can cause significant bronchoconstriction. Examples:

• Propranolol, nadolol, carvedilol (non-selective — most problematic)
• Metoprolol, atenolol, bisoprolol (cardioselective — generally safer but still use with caution)
• Ophthalmic beta-blockers (timolol eye drops) can have systemic absorption and interact

Moderate Interaction: Tricyclic Antidepressants (TCAs) and MAOIs

Tricyclic antidepressants (amitriptyline, nortriptyline, imipramine) and MAOIs (phenelzine, tranylcypromine) can potentiate the cardiovascular effects of salmeterol — increasing the risk of QT prolongation and arrhythmias. Wixela Inhub should be used with extreme caution in patients on these medications, and your cardiologist or prescriber should be aware.

Moderate Interaction: Diuretics

Loop diuretics (furosemide) and thiazide diuretics (hydrochlorothiazide) can cause hypokalemia (low blood potassium). Salmeterol can also lower potassium levels. The combination may cause additive hypokalemia, increasing the risk of muscle weakness and heart rhythm problems. Blood potassium should be monitored in patients on both therapies.

Food and Supplement Interactions

No clinically significant food interactions have been documented for Wixela Inhub at standard doses. Grapefruit juice inhibits CYP3A4 and theoretically could increase fluticasone exposure, but the clinical relevance of this is considered low for inhaled administration. As a general precaution, patients on Wixela Inhub who consume large amounts of grapefruit juice should mention this to their doctor.

What to Tell Your Doctor and Pharmacist

Before starting Wixela Inhub, tell your prescriber about every medication you take — including prescription drugs, over-the-counter medications, vitamins, supplements, and herbal products. Be especially sure to mention if you take any HIV medications, antifungals, antidepressants, beta-blockers, or blood pressure medications. For a complete overview of side effects to watch for, see: Wixela Inhub Side Effects: What to Expect and When to Call Your Doctor.