What Is Ketorolac Tromethamine Ophthalmic Solution?

Ketorolac tromethamine ophthalmic solution is a prescription eye drop that fights pain and inflammation without using a steroid. It belongs to the nonsteroidal anti-inflammatory drug (NSAID) family and works by blocking the enzymes that produce prostaglandins, the chemical messengers responsible for swelling, redness, and pain in the eye. Available in concentrations of 0.4%, 0.45%, and 0.5%, it has become one of the most widely used topical NSAIDs in eye care, prescribed for everything from seasonal allergy symptoms to post-surgical recovery. How well it stacks up against steroids and newer NSAID alternatives, though, depends heavily on the situation.

How It Works Inside the Eye

Ketorolac blocks cyclooxygenase enzymes, which are the body’s main machinery for producing prostaglandins. There are two main types of these enzymes. Ketorolac is roughly six times more active against COX-1 than COX-2, which distinguishes it from some newer ophthalmic NSAIDs like bromfenac that lean heavily toward COX-2 inhibition.¹ In practical terms, both approaches shut down prostaglandin production in the front of the eye effectively. That prostaglandin suppression is what reduces pain, limits fluid leakage into inflamed tissues, and keeps the pupil from constricting during surgery.

When you instill a drop, most of the drug concentrates in the cornea and the white outer shell of the eye, with smaller amounts reaching the fluid-filled chamber behind the cornea. Drug levels in that chamber run about 13 times higher than in the bloodstream after a topical dose, meaning the drug stays where it is needed rather than flooding the rest of the body.² Peak drug levels in eye tissues are typically reached within about an hour of instillation. The drug is absorbed systemically after eye-drop use, but because the dose is tiny, blood levels remain very low.

Treating Allergic Conjunctivitis

Seasonal allergic conjunctivitis, the itchy, red, watery eyes triggered by pollen, was one of ketorolac’s earliest approved indications. In clinical trials, the 0.5% formulation provided relief from itching, redness, swelling, and the gritty foreign-body sensation that comes with eye allergies. By roughly one week, treated eyes showed improvements across every major symptom category compared to placebo drops.³ The lower-concentration 0.4% version has also proven effective for allergies, both as a standalone treatment and alongside steroids when symptoms are stubborn.⁴

How does it compare to other NSAID eye drops for allergies? Head-to-head trials with diclofenac sodium 0.1% found that both drugs brought prompt symptom relief within about three days and sustained that relief for at least two weeks.⁵ For most people with garden-variety eye allergies, ketorolac offers a steroid-free alternative that avoids the pressure spikes and infection risks that come with long-term steroid eye-drop use.

Use After Cataract Surgery

Cataract surgery is probably where ketorolac tromethamine ophthalmic solution sees its heaviest use. Surgeons prescribe it to manage two things: the pain and inflammation that follow the procedure, and a complication called cystoid macular edema, where fluid accumulates in the central retina and blurs vision.

For pain, the results are clear. In one large trial of the 0.45% formulation (sold as Acuvail), about 72% of patients reported zero pain on the first day after surgery, compared with 40% in the placebo group. The median time to complete pain resolution was one day with the drug versus two days without it.⁶ Ketorolac also reduced the clinical signs of inflammation, including cell and protein leakage in the front chamber, redness, and light sensitivity.⁷

For preventing cystoid macular edema, the picture is more complicated. The 0.4% formulation has been shown to be comparable to the older 0.5% version in controlling post-cataract inflammation and preventing this complication.⁸ However, at least one randomized trial found no difference between ketorolac and placebo for preventing cystoid macular edema after uncomplicated cataract surgery, with similar rates of the condition (around 5% in both groups) and no significant difference in visual acuity outcomes.⁹ This is a genuine area of debate: many surgeons still prescribe ketorolac prophylactically because larger observational data suggest benefit, but the randomized evidence in straightforward, complication-free cases is not as strong as you might expect.

Maintaining Pupil Dilation During Surgery

Beyond postoperative care, ketorolac also plays a role during the operation itself. Prostaglandins released during surgical manipulation cause the pupil to constrict, which makes the surgeon’s job harder. Pre-operative ketorolac drops counteract this. Trials have demonstrated that ketorolac-treated eyes maintained significantly larger pupil diameters throughout surgery compared to vehicle drops.¹⁰ Adding ketorolac or another NSAID to the standard steroid-only regimen reduces this intraoperative pupil shrinkage more effectively than steroids alone.¹¹

How It Compares to Steroids

The rivalry between NSAID drops and steroid drops like prednisolone acetate is one of the running debates in post-cataract care. The good news for patients who are concerned about steroid side effects: ketorolac holds up well. Trials comparing ketorolac 0.5% directly to prednisolone acetate 1% after cataract surgery found comparable reductions in inflammation, pain, and visual recovery, with no significant changes in eye pressure in either group.¹²

A randomized clinical trial published in JAMA Ophthalmology took this a step further, comparing NSAID monotherapy against the common practice of combining prednisolone with an NSAID. The study found no meaningful difference in retinal thickness or visual acuity at any postoperative visit. Eye pressure was actually lower in the NSAID-only group at three days and three weeks after surgery.¹³ These findings suggest that for many uncomplicated cataract patients, an NSAID alone may be enough, potentially sparing them the elevated eye pressure that steroids can cause.

That said, when cystoid macular edema does develop after surgery, combination therapy appears to shine. In a small trial of patients with established pseudophakic cystoid macular edema, those receiving both ketorolac and prednisolone together gained an average of 3.8 lines of visual acuity, compared with 1.6 lines for ketorolac alone and 1.1 lines for prednisolone alone. Nearly 90% of the combination group achieved a meaningful two-line improvement.¹⁴ So while routine use of both drugs together may not add much over an NSAID alone, treating an actual complication seems to warrant the pairing.

How It Stacks Up Against Other NSAID Eye Drops

Ketorolac is not the only NSAID eye drop on the market. Nepafenac, bromfenac, and diclofenac are all competitors, and the question of which one is “best” has generated a small mountain of comparative research.

A meta-analysis of randomized trials comparing nepafenac and ketorolac after cataract surgery found both equally effective at controlling inflammation, reducing macular swelling, and improving vision. Nepafenac had a comfort advantage, though, causing less redness and less of the stinging sensation patients commonly associate with ketorolac.¹⁵ A network meta-analysis that compared all the major NSAID drops ranked diclofenac as most likely to reduce post-cataract inflammation, with nepafenac close behind. Ketorolac placed in the middle of the pack, ahead of flurbiprofen but behind nepafenac and bromfenac for pain relief.¹⁶

A separate head-to-head trial measuring inflammation by laser flare photometry found that nepafenac produced a greater reduction in anterior chamber flare at one month compared with ketorolac and bromfenac.¹⁷ These differences are real but relatively modest. The practical takeaway is that all modern NSAID eye drops work for post-surgical inflammation. Ketorolac’s main handicap relative to its competitors is the stinging that some patients notice on instillation, something that led to the development of the lower-concentration 0.4% formulation, which contains 20% less active ingredient than the original 0.5% drop and is generally reported to sting less.¹⁸

Use After Laser Eye Surgery

Ketorolac is also commonly prescribed after photorefractive keratectomy (PRK), a type of laser vision correction that removes the surface layer of the cornea and leaves an open wound that must heal over several days. Pain during that healing window can be intense, and NSAID drops help take the edge off.

A double-masked study comparing nepafenac 0.1% and ketorolac 0.4% after PRK found no difference in corneal healing time (about four days for both) or in postoperative pain scores. Neither drug caused adverse effects on the healing surface.¹⁹ Similarly, a comparison of bromfenac 0.09% and ketorolac 0.4% after PRK found no differences in pain, burning, foreign-body sensation, photophobia, or healing rates.²⁰ One study did find that ketorolac-treated eyes healed faster than bromfenac-treated eyes, with average healing times of about five and a half days versus over seven days, respectively.²¹ The inconsistency between studies probably reflects differences in patient populations and dosing protocols, but ketorolac does not appear to slow corneal healing when used as directed.

Corneal Abrasions and Other Off-Label Uses

A scratched cornea is one of the more common eye injuries seen in emergency rooms, and ketorolac has been studied here too, though the use is considered off-label. In one randomized trial, patients with corneal abrasions who received ketorolac 0.5% reported less pain, less light sensitivity, and less foreign-body sensation one day after injury compared to a placebo group, and they returned to normal activities sooner.²² A separate trial found that while subjective symptom scores were not dramatically different with ketorolac, the treated group needed significantly fewer oral painkillers.²³

A Cochrane review of topical NSAIDs for traumatic corneal abrasions pooled results across trials and found that NSAID drops roughly halved the need for rescue oral painkillers in the first 24 hours, though the certainty of the evidence was rated low.²⁴ The drops did not speed up actual healing of the scratch, which makes sense since they target the inflammatory pain response rather than the tissue repair process.

Safety Concerns and Who Should Be Cautious

Ketorolac eye drops are generally safe when used at prescribed doses for a limited time, but there are real risks that deserve attention. The most common side effect is transient burning or stinging on instillation, which some patients describe as intense. This stinging is more pronounced with the older 0.5% formulation than with the 0.4% version.

The more serious concern involves the cornea. A case series described 18 eyes in 16 patients who developed corneal complications ranging from severe surface damage to outright perforation while using topical NSAIDs including ketorolac. Most of these patients had recent cataract surgery and were using steroid drops at the same time, and several had underlying conditions that predispose the cornea to melting, such as rheumatoid arthritis, Sjögren’s syndrome, or rosacea.²⁵ A case report of a young man who used ketorolac every hour (far more frequently than prescribed) after PRK described corneal ulceration and perforation that required a corneal transplant.²⁶ These are extreme outcomes, but they highlight that exceeding the prescribed dose or using the drops on already-compromised corneas can be dangerous.

People with aspirin sensitivity or the combination of asthma and nasal polyps should avoid ketorolac eye drops unless they know they tolerate aspirin without trouble. Even though the dose delivered to the bloodstream from an eye drop is small, cases of bronchospasm triggered by topical ophthalmic ketorolac have been reported.²⁷ This is the same cross-reactivity seen with oral NSAIDs, just arriving through an unexpected route.

Effects on Corneal Sensitivity

An interesting property of topical NSAIDs that is not always discussed with patients is their ability to temporarily reduce corneal sensitivity. The cornea is one of the most densely innervated tissues in the body, which is why even a tiny eyelash feels enormous when it gets trapped under a lid. Both ketorolac and diclofenac significantly decrease this sensitivity after instillation, with the effect growing with repeated drops. Once you stop using ketorolac, sensitivity returns to normal relatively quickly compared to diclofenac, where the numbing lingers longer.²⁸

This reduced sensitivity is a double-edged sword. On one hand, it contributes to the pain-relieving effect. On the other, a cornea that cannot feel damage properly is a cornea that might not signal problems in time. This is part of the rationale for keeping NSAID eye-drop courses short and sticking to prescribed dosing frequencies, especially after surgeries where the corneal surface is already vulnerable.

Pediatric Use

For children, the evidence for ketorolac eye drops is thinner and less encouraging than in adults. Two separate randomized trials tested topical ketorolac 0.5% for pain control after pediatric strabismus surgery (the procedure to correct misaligned eyes). Neither found a benefit. One trial reported no difference in pain scale scores, need for extra painkillers, or postoperative vomiting between ketorolac-treated and control groups.²⁹ A second trial reached the same conclusion, finding no improvement in postoperative pain compared to placebo.³⁰

It is worth noting that the researchers themselves pointed out the difficulty of measuring pain reliably in young children, so the negative results may partly reflect the limitations of the pain scales rather than true drug failure. Still, based on the available evidence, topical ketorolac does not appear to add meaningful pain control in this specific pediatric context. Its use in children for other indications, like post-cataract inflammation or allergic conjunctivitis, is less well studied, and prescribing in pediatric patients tends to be guided by adult data and clinical judgment rather than dedicated pediatric trials.

Formulation Differences and Practical Considerations

You may encounter ketorolac tromethamine ophthalmic solution under several brand names and concentrations, and the differences between them are worth understanding. The original 0.5% formulation (often known by the brand name Acular) was designed for allergic conjunctivitis and post-surgical inflammation. The 0.4% reformulation (Acular LS) was developed specifically to reduce the stinging and burning that many patients complained about, containing 20% less active drug while maintaining comparable anti-inflammatory effectiveness.³¹ The 0.45% preservative-free version (Acuvail) is packaged in single-use vials and was developed for patients who need to avoid preservatives, particularly those using multiple eye drops after surgery.

Preservatives matter more than most patients realize. The standard preservative in multi-dose ketorolac bottles is benzalkonium chloride, which is known to be somewhat toxic to the corneal surface with repeated use. In patients who are already applying antibiotic drops, steroid drops, and an NSAID four times a day after surgery, the cumulative preservative exposure adds up. The preservative-free single-use vials sidestep this issue but cost more. Research on formulation also suggests that the vehicle matters: oil-based and ointment preparations of ketorolac can deliver higher drug levels to the eye and sustain the effect longer than standard water-based drops, though these alternative formulations are not widely available commercially.³²

One practical tip that many patients are not told: refrigerating ketorolac eye drops before use can reduce the stinging sensation. Cold drops also provide a mild soothing effect that allergic conjunctivitis sufferers tend to appreciate. Whether you store them cold or at room temperature, the drops should be discarded after the expiration date, and multi-dose bottles should not be shared between eyes if one eye has an active infection.