Maxitrol Drug Interactions: What to Avoid and What to Tell Your Doctor

Maxitrol (neomycin/polymyxin B/dexamethasone ophthalmic) is a topical eye medication, which means most of its ingredients stay in the eye rather than entering the bloodstream in significant amounts. This makes systemic drug interactions much less likely than with oral medications. However, some interactions are still worth knowing — especially with longer courses of treatment or in patients with specific health conditions.

How Systemic Absorption Affects Interactions

When you apply Maxitrol eye drops correctly, a small amount of the medication can drain through the nasolacrimal duct into your nose and throat, where it may be absorbed into the bloodstream. This is called systemic absorption. The amount is typically small, but in patients using high doses (such as hourly drops for severe disease) or using Maxitrol for extended periods, systemic absorption can become clinically relevant.

To minimize systemic absorption, apply gentle pressure to the inner corner of your eye (the nasolacrimal punctum) for 1–2 minutes after each drop application. This simple technique can reduce systemic absorption by up to 50%.

Drug Interactions with Neomycin (Antibiotic Component)

Neomycin belongs to the aminoglycoside antibiotic class. The most clinically relevant interaction involves botulinum toxins:

Botulinum toxins (onabotulinumtoxinA/Botox, abobotulinumtoxinA/Dysport, rimabotulinumtoxinB/Myobloc): Aminoglycosides like neomycin can potentiate the neuromuscular effects of botulinum toxins. This is listed as a cautionary interaction — if you're receiving Botox injections (whether cosmetic or medical, such as for migraine, hyperhidrosis, or muscle spasm), tell your prescriber before starting Maxitrol.

Tissue-engineered skin grafts (e.g., Gintuit): Topical antibiotics including neomycin can degrade certain biologic wound-healing products. This is relevant only in very specific post-surgical wound care contexts and not typical for eye drop use.

Drug Interactions with Dexamethasone (Steroid Component)

The dexamethasone component poses the most relevant systemic interaction risks when absorbed in larger amounts:

CYP3A4 inhibitors (e.g., ketoconazole, ritonavir, clarithromycin, grapefruit): These drugs slow the breakdown of dexamethasone in the body. In patients on CYP3A4 inhibitors who use high doses of Maxitrol over extended periods, there is a theoretical risk of increased systemic dexamethasone levels, which could lead to Cushing's syndrome-like effects. This is mostly a concern with prolonged high-dose use.

NSAIDs (oral or ophthalmic): Using ophthalmic NSAIDs (like ketorolac/Acular) together with Maxitrol can, in rare cases, increase the risk of corneal thinning or perforation, especially in patients with pre-existing corneal disease.

Other corticosteroids (systemic or inhaled): Using Maxitrol alongside systemic steroids (prednisone, methylprednisolone) or inhaled steroids adds to total steroid burden. While the ophthalmic dose is typically small, patients on systemic steroids should inform their prescriber.

Diabetes medications: Systemic dexamethasone can raise blood glucose. With ophthalmic use, this is rarely a clinical issue, but diabetic patients using high-dose or prolonged Maxitrol should monitor their blood sugar.

Interactions with Other Eye Drops

If you're using other eye drops alongside Maxitrol:

Wait at least 5 minutes between different eye drops. Applying multiple eye drops too close together can wash out the first medication before it's absorbed.

Apply ointments last. If you're using both Maxitrol ointment and other eye drops, apply the drops first and the ointment last, as ointments can block absorption of subsequent drops.

Benzalkonium chloride sensitivity: Maxitrol suspension contains benzalkonium chloride (BAK) as a preservative. BAK can accumulate on soft contact lenses. Do not wear soft contact lenses during Maxitrol treatment. If you use other preserved eye drops, multiple BAK exposures can increase ocular surface irritation.

What to Tell Your Doctor Before Using Maxitrol

Before starting Maxitrol, make sure to tell your prescriber about:

Any allergy to neomycin, polymyxin, dexamethasone, or other aminoglycoside antibiotics (gentamicin, tobramycin, kanamycin, streptomycin)

Glaucoma or elevated eye pressure history

Diabetes

Pregnancy or breastfeeding

Current Botox or botulinum toxin treatments

Any antifungal medications (CYP3A4 inhibitors such as ketoconazole or itraconazole)

Any corticosteroids you're already taking (oral, inhaled, or skin creams)

For more detail on what to watch for during treatment, see our companion guide: Maxitrol Side Effects: What to Expect and When to Call Your Doctor.