Ketorolac, sold under the brand name Toradol, Acular and Sprix, among others, is a nonsteroidal anti-inflammatory drug (NSAID) used to treat pain.

As a very potent prostaglandin inhibitor, ketorolac diminishes the kidney's own defenses against vasoconstriction-related effects, e.g. during blood loss or high endogenous catecholamine levels.

[15]: 280 Ketorolac is effective when administered with paracetamol (acetaminophen) to control pain in newborns because it does not depress respiration as do opioids.

Infrequent (<1%) side effects include paresthesia, prolonged bleeding time, injection site pain, purpura, sweating, abnormal thinking, increased production of tears, edema, pallor, dry mouth, abnormal taste, urinary frequency, increased liver enzymes, itching and others.

[15]: 279 Though uncommon, potentially fatal adverse effects include stroke, myocardial infarction, GI bleeding, Stevens–Johnson syndrome, toxic epidermal necrolysis and anaphylaxis.

Problematic GI effects are additive and become more likely if potassium supplements, aspirin, other NSAIDs, corticosteroids, or alcohol is taken at the same time.

The risk of bleeding increases with the concurrent medications clopidogrel, cefoperazone, valproic acid, cefotetan, eptifibatide, tirofiban, and ticlopidine.

The use of Panax ginseng, clove, ginger, arnica, feverfew, dong quai, chamomile, and Ginkgo biloba increases the risk of bleeding.

[25] The primary mechanism of action responsible for ketorolac's anti-inflammatory, antipyretic, and analgesic effects is the inhibition of prostaglandin synthesis by competitive blocking of the enzyme cyclooxygenase (COX).

[26] It is considered a first-generation NSAID,[15]: 279  a group of drugs that non-selectively inhibit both COX-1 and COX-2 enzymes, which can lead to gastrointestinal side effects.

[27] In contrast, later generations of NSAIDs are designed to selectively inhibit COX-2, aiming to reduce inflammation with fewer gastrointestinal issues.

[16] Acular, an ophthalmic formulation (eye-drop), was developed by the Syntex company, of Palo Alto, California around 2006, which is currently licensed by Allergan.

In the UK, treatment was initiated only in a hospital, although this was not designed to exclude its use in prehospital care and mountain rescue settings.

[36] Concerns over the high incidence of reported side effects with ketorolac led to its withdrawal (apart from the ophthalmic formulation) in several countries, while in others its permitted dosage and maximum duration of treatment have been reduced.

Competitive athletes, particularly in contact sports, are often expected by their coaches and/or teammates to play through injuries, generally with the help of painkillers.

[38][39] A lawsuit alleging widespread league-sanctioned abuse of painkillers was filed by former players against the National Football League in 2017.