Understanding What Not to Take with Latanoprost?

October 8, 2025 •

4 min read

According to the American Academy of Ophthalmology, millions of Americans have glaucoma, with a substantial number managing the condition with prostaglandin analog eye drops like latanoprost. It is crucial for these patients to understand what not to take with latanoprost to avoid potentially decreasing the medication's effectiveness and to prevent complications.

Quick Summary

This guide details important drug interactions and contraindications for latanoprost eye drops. It covers what medications to avoid, precautions for specific eye conditions, and crucial safety advice for patients using this glaucoma treatment.

Key Points

Avoid Other Prostaglandin Analogs: Do not use latanoprost alongside other prostaglandin eye drops (like bimatoprost or travoprost), as this can surprisingly reduce the IOP-lowering effect.
Separate Eye Drop Applications: If using other topical eye medications, ensure at least a 5-minute gap between applications to avoid interaction or 'wash-out'.
Remove Soft Contact Lenses: Take out soft contact lenses before using latanoprost, as its preservative (BAK) can stain them. Wait 15 minutes before reinserting.
Be Cautious with Eye Inflammation: Patients with active intraocular inflammation (uveitis/iritis) or active herpes simplex keratitis should generally avoid latanoprost, as it can worsen inflammation.
Never Double a Dose: Using more than one drop per day can reduce efficacy. If a dose is missed, simply take the next one at the usual time.
Monitor for Eye Changes: Be aware that latanoprost can cause permanent eye color changes and reversible changes to eyelashes. Discuss any concerns with your doctor.

Drug Interactions and Contraindications for Latanoprost

Latanoprost is a highly effective medication for reducing elevated intraocular pressure in patients with open-angle glaucoma or ocular hypertension. However, like all medications, it comes with important safety considerations, including specific drug interactions and contraindications. Ignoring these can compromise treatment efficacy and patient safety.

Other Prostaglandin Analogs

One of the most critical drug interactions involves combining latanoprost with other prostaglandin analogs. The simultaneous use of two or more prostaglandins or prostaglandin analogs is not recommended because it can actually diminish the intraocular pressure (IOP) lowering effect or even cause a paradoxical increase in eye pressure. These include medications like:

Bimatoprost (Lumigan®)
Travoprost (Travatan Z®)
Tafluprost (Zioptan®)
Latanoprostene bunod (Vyzulta®)

Thimerosal-Containing Eye Drops

Another crucial interaction to be aware of involves eye drops that contain thimerosal, a preservative. In vitro studies have demonstrated that when eye drops containing thimerosal are mixed with latanoprost, precipitation can occur. To avoid this, and to ensure proper absorption and effectiveness of any topical eye medication, multiple drops should be administered at least five minutes apart.

Ophthalmic Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

Some reports indicate that certain ophthalmic NSAIDs may interact with latanoprost, particularly when treating cystoid macular edema. While the interaction may not be severe in all cases, patients using both types of eye drops should do so with caution and under close medical supervision. Examples of ophthalmic NSAIDs include:

Diclofenac
Flurbiprofen
Ketorolac
Nepafenac

Important Precautions and Warnings

Beyond direct drug interactions, several patient-specific conditions and practices warrant special precautions or make latanoprost use inappropriate.

Avoid During Active Eye Inflammation

Latanoprost should not be used in patients with active intraocular inflammation, such as iritis or uveitis, as it may exacerbate the condition. It is also recommended to use it with caution in individuals with a history of intraocular inflammation.

History of Herpes Simplex Keratitis

Patients with a history of herpes simplex virus (HSV) eye infections should be cautious, as there have been reports of HSV keratitis reactivation during latanoprost treatment. For cases of active herpes simplex keratitis, latanoprost use should be avoided.

Patients with Damaged Lenses or Macular Edema Risk

Caution is advised when prescribing latanoprost for patients who are aphakic (lacking a lens), pseudophakic with a torn posterior lens capsule, or with known risk factors for macular edema. Macular edema, including cystoid macular edema, has been reported in these patient groups.

Use with Soft Contact Lenses

Latanoprost ophthalmic solutions often contain the preservative benzalkonium chloride (BAK), which can be absorbed by soft contact lenses and potentially discolor them. Therefore, patients must remove their soft contact lenses before administering the drops and wait at least 15 minutes before reinserting them.

Severe or Uncontrolled Asthma

For patients with severe or poorly controlled asthma, latanoprost should be used with caution. Some reports indicate that treatment with latanoprost may lead to an exacerbation of asthma symptoms, though this is uncommon.

Using Latanoprost with Other Ophthalmic Medications

When multiple topical ophthalmic medications are part of a treatment plan, the order and timing of administration are critical. To prevent contamination and ensure each medication is absorbed correctly:

Remove soft contact lenses: Take out lenses before applying any eye drops. Wait at least 15 minutes to reinsert them.
Separate applications: Administer each different eye drop formulation at least five minutes apart. This prevents 'wash-out' of the medication and avoids potential precipitation.

Comparison of Latanoprost and Other Glaucoma Drugs


Feature	Latanoprost (Prostaglandin Analog)	Timolol (Beta-Blocker)	Brimonidine (Alpha-Agonist)
Mechanism of Action	Increases uveoscleral outflow, enhancing fluid drainage from the eye.	Decreases the production of aqueous humor fluid in the eye.	Reduces aqueous humor production and increases outflow.
Dosage Frequency	Once daily, typically in the evening.	Typically twice daily, but also available once daily.	Usually twice or three times daily.
Preservative-Free Option	Yes, preservative-free versions (e.g., Monopost®) exist for sensitive eyes.	Yes, preservative-free versions (e.g., Timoptic in Ocudose®) are available.	Yes, some formulations are available with a less irritating preservative (e.g., Purite® in Alphagan P®).
Key Contraindications	Active intraocular inflammation, hypersensitivity, history of HSV keratitis.	Some cardiac and respiratory conditions (e.g., severe asthma, heart block).	Contraindicated in children under 2; use with caution in those with cardiovascular disease.
Common Side Effects	Iris color change (permanent), eyelash changes, and redness.	Systemic effects like fatigue, slow heart rate, or low blood pressure.	Dry mouth, fatigue, and allergic conjunctivitis.

Conclusion

While latanoprost is a cornerstone treatment for glaucoma and ocular hypertension, safe and effective usage requires careful attention to potential interactions and specific patient conditions. The most critical concerns are avoiding other prostaglandin eye drops, separating the application of different topical solutions, and being mindful of contraindications related to eye inflammation, prior herpes infections, and the use of soft contact lenses. Always maintain open communication with your ophthalmologist or healthcare provider about all your medications, eye health, and potential risks to ensure the best possible outcome for your vision.

Frequently Asked Questions

Yes, you can use other types of glaucoma eye drops with latanoprost. However, you must administer them at least 5 minutes apart. You should not, however, use other prostaglandin analog eye drops (like bimatoprost or travoprost) at the same time.

If you have active intraocular inflammation, such as uveitis or iritis, you should generally avoid using latanoprost, as it can worsen your condition. For patients with a history of such inflammation, use latanoprost with caution.

Yes, but with caution. You must remove your soft contact lenses before applying the drops because the preservative benzalkonium chloride (BAK) can be absorbed by the lenses. Wait at least 15 minutes before reinserting them.

Some ophthalmic NSAIDs, like diclofenac, have been noted as potential interactions. You should always inform your doctor if you are using NSAID eye drops so they can monitor your treatment and manage any risk.

If you miss a dose, you should skip it and continue with your next dose at the regular time. Do not double up on your dose, as using more than one drop per day can reduce the medication's effectiveness.

Significant interactions between latanoprost and oral medications are less common due to the low systemic absorption of the eye drops. However, it is essential to inform your doctor of all medicines, vitamins, and supplements you are taking to ensure safety.

Latanoprost can cause a gradual, and potentially permanent, increase in brown pigment in the iris. This is a well-documented side effect, and you should discuss any concerns with your doctor. Pigmentation of the eyelids and lashes may be reversible.