Characterization of the analgesic and anti-inflammatory activities of ketorolac and its enantiomers in the rat.
(1/140)
The marked analgesic efficacy of ketorolac in humans, relative to other nonsteroidal anti-inflammatory drugs (NSAIDs), has lead to speculation as to whether additional non-NSAID mechanism(s) contribute to its analgesic actions. To evaluate this possibility, we characterized (R,S)-ketorolac's pharmacological properties in vivo and in vitro using the nonselective cyclooxygenase (COX) inhibitors [indomethacin (INDO) and diclofenac sodium (DS)] as well as the selective COX-2 inhibitor, celecoxib, as references. The potency of racemic (R,S)-ketorolac was similar in tests of acetic acid-induced writhing, carrageenan-induced paw hyperalgesia, and carrageenan-induced edema formation in rats; ID50 values = 0.24, 0. 29, and 0.08 mg/kg, respectively. (R,S)-ketorolac's actions were stereospecific, with (S)-ketorolac possessing the biological activity of the racemate in the above tests. The analgesic potencies for (R,S)-, (S)-, and (R)-ketorolac, INDO, and DS were highly correlated with their anti-inflammatory potencies, suggesting a common mechanism. (R,S)-ketorolac was significantly more potent than INDO or DS in vivo. Neither difference in relative potency of COX inhibition for (R,S)-ketorolac over INDO and DS nor activity of (S)-ketorolac at a number of other enzymes, channels, or receptors could account for the differences in observed potency. The distribution coefficient for (R,S)-ketorolac was approximately 30-fold less than for DS or INDO, indicating that (R,S)-ketorolac is much less lipophilic than these NSAIDs. Therefore, the physicochemical and pharmacokinetics properties of (R,S)-ketorolac may optimize the concentrations of (S)-ketorolac at its biological target(s), resulting in greater efficacy and potency in vivo. (+info)
Ketoprofen, diclofenac or ketorolac for pain after tonsillectomy in adults?
(2/140)
We have compared the analgesic and opioid sparing effect of three i.v. non-steroidal anti-inflammatory drugs with placebo in a randomized, double-blind, placebo-controlled study in 80 adult patients after elective tonsillectomy. A standard anaesthetic was used. After induction of anaesthesia, patients received ketoprofen 100 mg, diclofenac 75 mg or ketorolac 30 mg by i.v. infusion over 30 min. Patients in the placebo group received saline. Ketoprofen and diclofenac infusions were repeated after 12 h and ketorolac infusion at 6 h and 12 h. Oxycodone was used as rescue analgesic. Patients in the ketoprofen group requested 32% less opioid and patients in the diclofenac and ketorolac groups 42% less opioid than those in the placebo group (P < 0.05). There were one, two and six patients in the placebo, diclofenac and ketorolac groups, respectively, but none in the ketoprofen group, who did not request opioid analgesia during the study (P < 0.05, ketorolac vs placebo and ketoprofen). Visual analogue pain scores were similar in all groups. Visual analogue satisfaction scores were significantly higher in the diclofenac group compared with the placebo group. The incidence of nausea was 44-54%. There were no differences in the incidence of other adverse reactions. We conclude that all three non-steroidal anti-inflammatory drugs were superior to placebo after tonsillectomy. (+info)
I.v. diclofenac and ketorolac for pain after thoracoscopic surgery.
(3/140)
We studied intensity of pain, cumulative morphine consumption, ventilatory and renal function, and haemostasis in patients undergoing video-assisted thoracoscopic surgery and receiving a 2-day i.v. infusion of diclofenac, ketorolac or saline. Plasma concentrations of the two NSAID were also measured. The study was randomized, double-blind and placebo-controlled, with 10 patients in each group. Patients experienced mainly moderate pain. Mean consumption of i.v. morphine during the first day after operation was 57 (SEM 11) mg in the placebo group. Diclofenac and ketorolac were equally effective in reducing total morphine consumption (61% and 52%, respectively). Adverse events were similar and minor. Greater variability in plasma concentrations of ketorolac were detected compared with diclofenac. (+info)
Comparative effects of cyclo-oxygenase and nitric oxide synthase inhibition on the development and reversal of spinal opioid tolerance.
(4/140)
1. This study examined the effects of the COX inhibitors, ketorolac and ibuprofen, and the NOS inhibitor L-NAME for their potential to both inhibit the development and reverse tolerance to the antinociceptive action of morphine. 2. Repeated administration of intrathecal morphine (15 micrograms), once daily, resulted in a progressive decline of antinociceptive effect and an increase in the ED50 value in the tailflick and paw pressure tests. Co-administration of ketorolac (30 and 45 micrograms) or S(+) ibuprofen (10 micrograms) with morphine (15 micrograms) prevented the decline of antinociceptive effect and increase in ED50 value. Similar treatment with L-NAME (100 micrograms) exerted weaker effects. Administration of S(+) but not R(-) ibuprofen (10 mg kg-1) had similar effects on systemic administration of morphine (15 mg kg-1). 3. Intrathecal or systemic administration of the COX or NOS inhibitors did not alter the baseline responses in either tests. Acute keterolac or S(+) ibuprofen also did not potentiate the acute actions of spinal or systemic morphine, but chronic intrathecal administration of these agents increased the potency of acute morphine. 4. In animals already tolerant to intrathecal morphine, subsequent administration of ketorolac (30 micrograms) with morphine (15 micrograms) partially restored the antinociceptive effect and ED50 value of acute morphine, reflecting the reversal of tolerance. Intrathecal L-NAME (100 micrograms) exerted a weaker effect. 5. These data suggest that spinal COX activity, and to a lesser extent NOS activity, contributes to the development and expression of opioid tolerance. Inhibition of COX may represent a useful approach for the prevention as well as reversal of opioid tolerance. (+info)
Effects of selective and unselective cyclooxygenase inhibitors on prostanoid release from various rat organs.
(5/140)
It has been assumed that cyclooxygenase-2 (COX-2) is solely responsible for inflammatory processes. Recently, this view has been challenged because COX-2-selective agents caused a delay of gastric ulcer healing and exacerbation of inflammation in rats. To further characterize organ-specific toxic effects of selective and nonselective COX inhibitors, we assessed the eicosanoid release from different rat organs ex vivo after oral administration of the COX-2-selective inhibitor NS-398 and the unselective COX inhibitors diclofenac, meloxicam, and ketorolac. Prostanoid and leukotriene release from tissue fragments of the stomach, kidney, lung, and brain were determined after ex vivo incubation of tissue fragments in Tyrode's solution for 10 min at 37 degrees C. Ketorolac (0.1, 0.3, and 0.9 mg/kg) inhibited prostanoid release from all organs most potently and led to a significant increase of leukotriene release from the lung. Effects of diclofenac and meloxicam (1, 3, and 9 mg/kg each) were similar for all organs tested. At 9 mg/kg, 6keto-prostaglandin F (PGF)(1alpha) release from gastric mucosa was reduced by 79.1 +/- 11.4 and 87.6 +/- 7.7% and PGE(2) release from rat kidney was inhibited by 60.4 +/- 6.8 and 78.6 +/- 16.6% by diclofenac and meloxicam, respectively. NS-398 did not reduce prostanoid release from the lung. Consistent with the reported constitutive expression of COX-2, prostanoid release from kidney and brain was reduced by 20 to 30%. The release of 6keto-PGF(1alpha) from gastric mucosa was reduced by 34.7 +/- 22.2% at 3 mg/kg and by 86.9 +/- 12.7% at 9 mg/kg. At these doses, NS-398 has been previously shown to be COX-2 selective. Because PGF(1alpha) is the stable breakdown product of PGI(2), these results suggest that COX-2 contributes to PGI(2) synthesis in the rat stomach. (+info)
Single-dose ketorolac and pethidine in acute postoperative pain: systematic review with meta-analysis.
(6/140)
For a systematic review of postoperative analgesic efficacy and adverse effects of single doses, injected or oral, of pethidine and ketorolac compared with placebo, we sought published randomized studies in moderate to severe postoperative pain. Information on summed pain intensity or pain relief outcomes over 4-6 h was extracted and converted to dichotomous information to produce the number of patients with at least 50% pain relief. This was used to calculate the relative benefit and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. Minor and major adverse effect data were extracted and summarized. For pethidine 100 mg i.m., eight randomized, controlled studies met the inclusion criteria, with 203 patients given pethidine and 161 placebo. The NNT to produce at least 50% pain relief was 2.9 (95% confidence interval 2.3-3.9). At this dose, pethidine produced significantly more drowsiness and dizziness than placebo, with numbers-needed-to-harm (NNH) of 2.9 (2.2-4.4) and 7.2 (4.8-14), respectively. For ketorolac, 14 reports met the inclusion criteria (six i.m. and eight oral). Most i.m. information (176 patients) was available for the 30 mg dose, which had an NNT of 3.4 (2.5-4.9). Most oral information was available for the 10 mg dose, which had an NNT of 2.6 (2.3-3.1). Oral ketorolac 10 mg was consistently at least as effective as ketorolac 30 mg i.m. Only with oral ketorolac 10 mg were there significantly more adverse effects than with placebo, with an NNH for any adverse effect of 7.3 (4.7-17). (+info)
Effect of continuous epidural 0.2% ropivacaine vs 0.2% bupivacaine on postoperative pain, motor block and gastrointestinal function after abdominal hysterectomy.
(7/140)
We have investigated the effect of 24-h postoperative continuous epidural infusion of 0.2% ropivacaine or 0.2% bupivacaine 8 ml h-1 on pain, request for supplementary analgesics, motor block and gastrointestinal function, in a double-blind, randomized study in 60 patients undergoing open hysterectomy. There were no significant differences between groups in pain, number of patients requesting supplementary analgesics, motor block, ability to walk or time to first flatus or stool. In the subgroup of patients who received supplementary analgesics, patients in the ropivacaine group received significantly more ketorolac than patients in the bupivacaine group. Time to discharge from hospital was similar with ropivacaine and bupivacaine. (+info)
Cyclooxygenase regulates human oropharyngeal carcinomas via the proinflammatory cytokine IL-6: a general role for inflammation?
(8/140)
High levels of prostaglandins are produced in human oropharyngeal carcinoma (OPC). Five human OPC cell lines tested expressed both isoforms of cyclooxygenases (COX). The pan-COX inhibitor ketorolac continuously and significantly decreased PGE(2) production and IL-6 and IL-8 levels in all OPC cell lines tested, but did not affect IL-1alpha, GM-CSF levels, or in vitro tumor cell growth. In contrast, ketorolac reduced OPC growth in vivo. The OPC cell lines used express the IL-6 receptor, and IL-6 stimulation of these cells causes transduction to occur via STAT3 pathway activation. Coincubation with OPC cell lines with conditioned medium from a TPA-exposed HL-60 cells stimulated growth proportional to the IL-6 levels measured in the conditioned medium. This growth effect was specifically inhibited by anti-IL-6 antibody. These results are consistent with cytokine products of inflammatory cells having paracrine growth effects on OPC. If chronic inflammation plays a role in promoting the development of OPC, this mechanism may also apply to other epithelial tumor systems modulated by COX activity. (+info)