Ketorolac

Ketorolac is a non-steroidal anti-inflammatory drug (NSAID) in the family of propionic acids, often used as an analgesic, antipyretic (fever reducer), and anti-inflammatory. Ketorolac acts by inhibiting bodily synthesis of prostaglandins. Ketorolac in its oral and intramuscular preparations is a racemic mixture of (S)-(−)-ketorolac, the active isomer, and (R)-(+)-ketorolac. An ophthalmic solution of ketorolac is available under the name Acular, and is used to treat eye pain and to relieve the itchiness and burning of seasonal allergies.

Mechanism of action

The primary mechanism of action responsible for Ketorolac's anti-inflammatory/antipyretic/analgesic effects is the inhibition of prostaglandin synthesis by competitive blocking of the the enzyme cyclooxygenase (COX). Like most NSAIDs, Ketorolac is a non-selective cyclooxygenase inhibitor.

As with other NSAIDs, the mechanism of the drug is associated with the chiral S form. Conversion of the R enantiomer into the S enantiomer has been shown to occur in the metabolism of ibuprofen; it is unknown whether it occurs in the metabolism of ketorolac.

Indications

Ketorolac is indicated for short-term management of pain (up to five days maximum).

Contraindications

Ketorolac is contraindicated against patients with a previously demonstrated hypersensitivity to ketorolac, and against patients with the complete or partial syndrome of nasal polyps, angioedema, bronchospastic reactivity or other allergic manifestations to aspirin or other non-steroidal anti-inflammatory drugs (due to possibility of severe anaphylaxis). As with all NSAIDs, ketorolac should be avoided in patients with renal dysfunction. (Prostaglandins are needed to dilate the afferent arteriole; NSAIDs effectively reverse this.) The patients at highest risk, especially in the elderly, are those with fluid imbalances or with compromised renal function (e.g., heart failure, diuretic use, cirrhosis, dehydration, and renal insufficiency).