Merck’s AzaSite ophthalmic solution can help restore healthy ocular surfaces in patients.
AzaSite®, which is distributed by Merck who recently acquired Inspire Pharmaceuticals, Inc., allows my patients to get the benefits of a localized ocular surface treatment with a highly effective antimicrobial—azithromycin—while simultaneously receiving significant anti-inflammatory activity on both the ocular surface and eyelid tissues.
AzaSite not only attacks the most common pathogens, namely Staphylococcus, Streptococcus, and Hemophilus, but it adds the additional action of interrupting the inflammatory cascade. It suppresses cytokines and chemokines and other inflammatory constituents, and it reduces matrix metalloproteinase (MMP). It does all this anti-inflammatory activity without the risk of slowing the healing process or higher intraocular pressure that comes with topical corticosteroids.
Another benefit I’ve found with AzaSite is its seven-day dosing schedule for bacterial conjunctivitis. The regimen is only nine drops—two a day for the first two days, then once a day for the remaining five days. Typically, topical antibacterials require four-times-a-day application, if not more, for a loading dose. Compliance is a big issue, especially with younger children, but AzaSite’s simplified dosing schedule resolves that in many cases.
The FDA approved AzaSite for treating bacterial conjunctivitis. I use it as a first-line treatment for bacterial conjunctivitis in children aged 1 and older because of the effect and the dosing schedule. I also use it off-label as a first-line treatment in patients with significant inflammatory lid disease (blepharitis and meibomitis) and secondary dry eye and ocular surface inflammation.
Azithromycin accumulates in the tissues in much higher concentrations than a fluoroquinolone so AzaSite can be used for a longer term pulse therapy and safer than a topical corticosteroid. AzaSite is analogous to oral tetracycline, but only delivers the benefits of localized treatment while avoiding systematic side effects. It provides a sustained concentration of drug where it’s needed, be it the lids, cornea, conjunctiva, or tears.
With antibacterial drugs, resistance is always a concern but more so with systemic drugs due to greater volume of the drug involved. Even with
|COMMENTS FROM THE DOCS
“I’ve had great success using this medication for acute blepharitis, especially meibomian gland dysfunction. The immunomodulatory mechanisms inherent to azithromycin help to provide rapid, quantifiable clinical improvement of lid margin inflammation, usually within two to four weeks.”
—Alan G. Kabat, OD,
Nova Southeastern University College
of Optometry, Ft. Lauderdale, FL
—Paul M. Karpecki, OD,
Koffler Vision Group, Lexington, KY
topical azithromycin, proper dosing is important because subtherapeutic dosing promotes mutation, thereby increasing the likelihood of resistance. Be mindful also that resistance can be an issue when using AzaSite long-term for inflammatory lid disease.
Allergy may also be an issue when prescribing azithromycin, but in some
patients what can look like an allergic reaction may not be so. Gastrointestinal upset can masquerade as anaphylaxis, so it’s important to differentiate between these two and rule out an allergy.
AzaSite has brought the one-two punch of azithromycin to optometry’s medical tool chest.
Maynard Pohl is clinical director at Pacific Cataract & Laser Institute, Bellevue, WA.
WHERE TO FIND IT:
Merck • 908-423-1000 • azasite.com