What drugs should not be taken with latanoprost?

October 9, 2025 •

4 min read

According to the FDA, administering two or more prostaglandin analogs at once can decrease the intraocular pressure-lowering effect or cause paradoxical elevations in pressure. This is the most critical interaction to avoid when considering what drugs should not be taken with latanoprost, but other interactions and precautions are also important to discuss with a healthcare provider.

Quick Summary

Combining latanoprost with certain eye drops, particularly other prostaglandin analogs, can increase intraocular pressure. Other precautions include separating administration times for other topical eye medications and avoiding it with active eye infections.

Key Points

Avoid other prostaglandin eye drops: Do not use latanoprost with other prostaglandin analogs like bimatoprost or travoprost, as this can increase eye pressure.
Wait 5 minutes between eye drops: Administering other topical ophthalmic drugs should be separated from latanoprost by at least 5 minutes to ensure proper absorption.
Separate from thimerosal: Mixing latanoprost with eye drops containing thimerosal can cause precipitation; use them separately.
Exercise caution with active inflammation: Patients with active intraocular inflammation (iritis/uveitis) or herpes keratitis should generally avoid latanoprost.
Remove contact lenses before use: Always remove contact lenses before applying latanoprost and wait at least 15 minutes before reinserting them.
Inform your doctor of all medications: Provide a complete list of all medications, including ophthalmic and systemic, to your healthcare provider for review.

The Primary Interaction: Prostaglandin Analogs

The most significant and well-documented drug interaction with latanoprost involves other medications from the same class: prostaglandin analogs. Combining different prostaglandin-based eye drops is not recommended and can be counterproductive for managing glaucoma and ocular hypertension. Latanoprost lowers intraocular pressure (IOP) by increasing the outflow of fluid from the eye. However, administering a second prostaglandin, such as bimatoprost (Lumigan) or travoprost (Travatan), can interfere with this mechanism and may lead to a paradoxical increase in IOP. This makes the combination not only ineffective but potentially dangerous for patients relying on the pressure-lowering effect.

Examples of Prostaglandin Analogs to Avoid

Bimatoprost (Lumigan): A notable interaction was documented in a case series where combining bimatoprost with latanoprost led to significant IOP elevation.
Travoprost (Travatan): Like bimatoprost, travoprost should not be used in conjunction with latanoprost.
Tafluprost (Zioptan): As another prostaglandin analog, tafluprost should also be avoided.
Latanoprostene bunod (Vyzulta): Combining this newer prostaglandin analog with latanoprost may also interfere with the IOP-lowering effect.

Interactions with Other Ocular Medications

While combining different prostaglandin analogs is contraindicated, latanoprost can be used with other classes of glaucoma medication, such as beta-blockers or carbonic anhydrase inhibitors. However, proper administration is crucial to avoid issues.

Proper Spacing: The golden rule for using multiple topical eye medications is to separate them by at least five minutes. This prevents one medication from washing out the other and ensures each has time to be absorbed effectively.
Thimerosal-Containing Drops: In vitro studies have shown that eye drops containing the preservative thimerosal can cause precipitation when mixed with latanoprost. To avoid this, and to prevent potential reduced efficacy, administer these drops separately, adhering to the 5-minute rule.

Non-Ocular Drugs and Latanoprost

Serious interactions between latanoprost and systemic (non-ocular) drugs are rare, but some potential interactions have been noted. The extensive lists found in some drug databases are largely theoretical or pertain to more complex interactions, but it is always best to keep your healthcare provider informed.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Some NSAIDs, especially in their ophthalmic form, have been shown to potentially decrease the therapeutic efficacy of latanoprost. While this is usually less concerning than combining prostaglandin analogs, it's worth discussing with your ophthalmologist if you use NSAID eye drops.
Certain Systemic Medications: Some systemic drugs, like Baricitinib, have been noted to potentially increase serum concentration when combined with latanoprost, though the clinical significance of these types of interactions is often low for topical eye drops. Always inform your doctor of all your systemic medications, vitamins, and supplements.

Comparison Table: Common Interacting Ocular Medications


Medication Class	Specific Examples	Nature of Interaction	How to Manage
Prostaglandin Analogs	Bimatoprost, Travoprost, Tafluprost	Can paradoxically increase intraocular pressure and reduce overall efficacy.	Avoid combining prostaglandin analogs.
Thimerosal-containing Eye Drops	Various brands (check label)	May cause precipitation when mixed directly with latanoprost in the eye.	Administer at least 5 minutes apart to avoid direct contact.
Other Topical Ophthalmic Drugs	Beta-blockers, carbonic anhydrase inhibitors	May have reduced absorption and efficacy if not administered separately.	Administer at least 5 minutes apart.
Ophthalmic NSAIDs	Diclofenac, Ketorolac	Potential for reduced efficacy of latanoprost.	Inform your doctor if using ophthalmic NSAIDs. Follow dosage instructions carefully.

Contraindications and Special Conditions

Certain medical conditions and patient situations also represent important considerations for latanoprost use.

Active Intraocular Inflammation (Iritis/Uveitis): Latanoprost can exacerbate inflammation, so it should be used with extreme caution or avoided in patients with active intraocular inflammation.
Herpetic Keratitis: Reactivation of herpes simplex keratitis has been reported in patients using latanoprost. Use should be avoided in cases of active herpes infections of the eye and used with caution in those with a history of the condition.
Risk Factors for Macular Edema: Patients with risk factors for macular edema, such as aphakic patients or those with a torn posterior lens capsule, should use latanoprost with caution.
Hypersensitivity: Any patient with a known allergy to latanoprost or its ingredients, including the preservative benzalkonium chloride, should not use the medication.

Conclusion

Understanding which medications and conditions interact negatively with latanoprost is vital for ensuring its effectiveness and safety. The most crucial rule is to never combine it with another prostaglandin analog eye drop, as this can paradoxically raise eye pressure. Beyond this, a healthcare provider should be fully aware of all other eye drops and systemic medications being used to prevent less severe but still important interactions. Always follow your doctor's instructions carefully and report any unusual symptoms immediately to maintain the best possible outcome for your eye health.

For more information on latanoprost and its prescribing information, consult the National Institutes of Health (NIH) bookshelf publication on Latanoprost.

Frequently Asked Questions

Yes, you can use latanoprost with other classes of eye drops like beta-blockers. However, it is essential to wait at least five minutes between administering each medication to prevent one from washing out the other.

Combining latanoprost with other prostaglandin analogs, such as bimatoprost, can interfere with its mechanism of action and may cause a paradoxical increase in your intraocular pressure. This is a serious interaction that defeats the purpose of the medication.

If you accidentally mix them, especially with a thimerosal-containing drop, precipitation can occur. While often not an emergency, it is best to rinse your eye gently and administer the drops again with the proper five-minute spacing. Always inform your doctor.

The interaction between latanoprost and oral NSAIDs is considered less severe than with ophthalmic NSAIDs. However, it is still important to inform your doctor about all medications you take, including over-the-counter ones, to ensure no unintended effects occur.

Patients with active herpes simplex keratitis or intraocular inflammation (iritis/uveitis) should avoid latanoprost. It should also be used with caution in patients with known risk factors for macular edema.

Remove your contact lenses before applying latanoprost eye drops. Wait at least 15 minutes after administration before reinserting them, as the preservative in some formulations can be absorbed by the lenses.

If you miss a dose, simply skip it and continue with your regular once-daily schedule the following evening. Do not double up on doses, as more frequent administration can reduce its effectiveness.