BAK in eye drops

BAK is the most commonly used eye drop preservative. Learn why BAK is BAD for the ocular surface, and how to find alternatives.

  • Benzalkonium chloride, the most commonly used preservative in eye drops.

  • 1: It's in most prescription eye drops, and many over the counter eye drops, particularly redness relievers and generic eye drops of all kinds.

    2: It's known to cause or exacerbate dry eye in multiple ways.

    Benzalkonium chloride (BAK) is a common preservative that is believed to be damaging to the eyes in up to seven different ways, according to TFOS DEWS II's Iatrogenic Dry Eye Report (see section 4.2.3.1).

    This preservative is used in most prescription eye drops and it is also used in many over-the-counter eyedrops without any warning on the label that mentions the preservative.

    Consumers over OTC eye drops sometimes use drops with BAK every day for years without any idea of the long term side effects, on the assumption that if it is sold over the counter, it must be safe.

    Consumers who are taking prescription eye drops on a daily basis for long periods are often similarly unaware of the ocular surface risks involved.

  • Don't: Please don't stop taking a drug your doctor prescribed just because it's on this list!

    Don't: Assume that if it's not on this list then it's OK. These lists are not exhaustive. Check the label to be sure.

    Do: Look up your eye drops to see if any of them have BAK.

    Do: Bear in mind that while I have included active ingredients so that you can find equivalents and generics, equivalents and generics may be different from the original name brand - they may have a different preservative, or have a different concentration of the preservative.

    Do: Have a conversation with your eye doctor to see if there is an alternative that is either preservative-free or contains a less harmful preservative.

    A conversation may seem like a small thing. IT'S NOT SMALL. Our collective conversations are our most powerful tools to influence the eye care professions and the industries that cater to them and us, which can change the future of eye care and reduce the incidence of preventable dry eye caused by preservatives.

    So please, talk, ask questions, and keep the conversation about preservatives flowing.

Prescription eye drops

Please use this information responsibly. Do not stop taking a medication that you have been prescribed without consulting your eye care provider. If you are concerned about BAK in a prescription medication, please ask your eye care provider if there are alternatives that will be equally effective.

Glaucoma medications

  • Xalatan (latanoprost) - Pfizer

  • Travatan (travoprost) - Alcon

    Rescula (unoprostone isopropyl) - Ciba Vision

  • Timoptic (timolol maleate - Merck)

    Betoptic S (betaxolol) - Alcon

    Azopt (brinzolamide) - Alcon

  • Cosopt (dorzolamide) - Merck

    Trusopt (dorzolamide) - Merck

  • Alphagan (brimonidine tartrate) - Bausch & Lomb

    Istalol (timolol maleate) - Bausch & Lomb

    Lumigan (bimatoprast) - Allergan

  • Betagan (levobunolol) - Allergan

  • Travatan Z (travoprost) - Alcon

  • Alphagan P (brimonidine tartrate 0.1%) - Allergan

  • Cosopt PF (dorzolamide hydrochloride and timolol maleate) - Théa Pharma

    Timoptic 0.25% and 0.5% in Ocudose (timolol maleate) - Merck

    Zioptan (tafluprost 0.005%) - Théa Pharma

Steroid medications

  • This information waas redacted from Pred Forte’s MSDS. If you have a US-based source for Pred Forte’s BAK concentration, please let us know.

Other common Rx eye drops

  • Item description

  • Durezol is preserved with sorbic acid

Over-the-counter eye drops

Unfortunately, the FDA does not require manufacturers of over-the-counter eye medications to disclose the concentration of any inactive ingredients, including preservatives. As a result, we do not know the BAK concentration for most OTC eye drops. The exceptions are OTC eye drops which were originally prescription medications; OTC eye drops which have gone through the FDA’s drug approval process for other reasons (rare); and eye drops whose manufacturer provided us with this information on request. Most have declined.

Allergy eye drops with BAK

Redness Reliever Eye Drops

Lubricant Eye Drops with BAK

  • All Clear Eyes brand eye drops are preserved with an unspecified concentration of BAK, with one exception: “Clear Eyes Sensitive”, which lists polyaminopropyl biguanide as preservative.

  • Lumify is preserved with 0.01% BAK.

  • Most Visine brand eye drops, including lubricants, are preserved with an unspecified concentration of BAK.

    The following Visine redness reliever eye drops are preserved instead with polyquaternium-42:

    • Visine Red Eye Comfort

    • Visine Red Eye Hydrating Comfort