Tenoxicam. An update of its pharmacology and therapeutic efficacy in rheumatic diseases

Efficacy of Tenoxicam, Paracetamol, and Their Combination in Postoperative Pain After Double-Jaw Surgery

Introduction Orthognathic surgical procedures include a series of surgical operations in which interventions are applied to the maxilla, mandible, or both for occlusal or aesthetic concerns due to facial skeletal development deformities. Double-jaw surgeries have the highest pain scores, in which both maxilla and mandible bones are intervened. This study aimed to compare the efficacy of individual applications of paracetamol and tenoxicam with their combined application on postoperative pain and opioid consumption in patients undergoing double-jaw surgery. Methods In this randomized, double-blind study, 60 patients undergoing double-jaw surgery were allocated into three groups, with each having 20 patients: the paracetamol group, the tenoxicam group, and the paracetamol-tenoxicam combination group. Pain intensity was evaluated using the visual analogue scale (VAS) at intervals of 30 minutes, 60 minutes, 120 minutes, and again at the 24th postoperative hour. Additionally, the consumption of opioids and other rescue analgesics was documented over the 24-hour postoperative period. Results The VAS values at 30 minutes, 60 minutes, and 24 hours were lower in the paracetamol-tenoxicam group compared to the other groups (p<0.001). The need for a rescue analgesic drug in the first 24 hours was not observed in the tenoxicam and paracetamol-tenoxicam groups. Conclusion It was concluded that both tenoxicam and paracetamol-tenoxicam combinations, especially the tenoxicam-paracetamol combination, were good options for postoperative analgesia in patients with double-jaw surgery.

Modulation of Inflammatory Mediators by Polymeric Nanoparticles Loaded with Anti-Inflammatory Drugs

The first-line treatment of osteoarthritis is based on anti-inflammatory drugs, the most currently used being nonsteroidal anti-inflammatory drugs, selective cyclooxygenase 2 (COX-2) inhibitors and corticoids. Most of them present cytotoxicity and low bioavailability in physiological conditions, making necessary the administration of high drug concentrations causing several side effects. The goal of this work was to encapsulate three hydrophobic anti-inflammatory drugs of different natures (celecoxib, tenoxicam and dexamethasone) into core-shell terpolymer nanoparticles with potential applications in osteoarthritis. Nanoparticles presented hydrodynamic diameters between 110 and 130 nm and almost neutral surface charges (between −1 and −5 mV). Encapsulation efficiencies were highly dependent on the loaded drug and its water solubility, having higher values for celecoxib (39–72%) followed by tenoxicam (20–24%) and dexamethasone (14–26%). Nanoencapsulation reduced celecoxib and dexamethasone cytotoxicity in human articular chondrocytes and murine RAW264.7 macrophages. Moreover, the three loaded systems did not show cytotoxic effects in a wide range of concentrations. Celecoxib and dexamethasone-loaded nanoparticles reduced the release of different inflammatory mediators (NO, TNF-α, IL-1β, IL-6, PGE₂ and IL-10) by lipopolysaccharide (LPS)-stimulated RAW264.7. Tenoxicam-loaded nanoparticles reduced NO and PGE₂ production, although an overexpression of IL-1β, IL-6 and IL-10 was observed. Finally, all nanoparticles proved to be biocompatible in a subcutaneous injection model in rats. These findings suggest that these loaded nanoparticles could be suitable candidates for the treatment of inflammatory processes associated with osteoarthritis due to their demonstrated in vitro activity as regulators of inflammatory mediator production.

Synthesis of Densely Substituted Sulfonylfurans and Dihydrofurans via Cascade Reactions of α-Functionalized Nitroalkenes with β-Ketosulfones

The reaction of β-ketosulfones with different α-functionalized nitroalkenes affords diversely substituted sulfonylfurans and dihydrofurans. Furthermore, β-ketosulfones react with α-bromonitroalkenes and α-hydrazinonitroalkenes via a cascade Michael addition-cyclization protocol to afford nitrodihydrofurans and hydrazinodihydrofurans, respectively, bearing a key sulfonyl group, in excellent yields with a broad substrate scope. Application of these products has been demonstrated by the synthesis of pyrroles and pyrazoles in good yields. The reaction of β-ketosulfones with nitroallylic acetates yields tetrasubstituted sulfonyl furans through a cascade S_N2'-intramolecular Michael reaction, followed by aromatization. The gram-scale synthesis of a representative example of sulfonylfurans was carried out to demonstrate the synthetic efficiency of the methodology.

Non-ionic Surfactant Based In Situ Forming Vesicles as Controlled Parenteral Delivery Systems

Non-ionic surfactant (NIS) based in situ forming vesicles (ISVs) present an affordable alternative to the traditional systems for the parenteral control of drug release. In this work, NIS based ISVs encapsulating tenoxicam were prepared using the emulsion method. Tenoxicam-loaded ISVs were prepared using a 2².3¹ full factorial experimental design, where three factors were evaluated as independent variables; type of NIS (A), molar ratio of NIS to Tween®80 (B), and phase ratio of the internal ethyl acetate to the external Captex® oil phase (C). Percentage drug released after 1 h, particle size of the obtained vesicles and mean dissolution time were chosen as the dependent variables. Selected formulation was subjected to morphological investigation, injectability, viscosity measurements, and solid state characterization. Optimum formulation showed spherical nano-vesicles in the size of 379.08 nm with an initial drug release of 37.32% in the first hour followed by a sustained drug release pattern for 6 days. DSC analysis of the optimized formulation confirmed the presence of the drug in an amorphous form with the nano-vesicles. Biological evaluation of the selected formulation was performed on New Zealand rabbits by IM injection. The prepared ISVs exhibited a 45- and 28-fold larger AUC and MRT values, respectively, compared to those of the drug suspension. The obtained findings boost the use of ISVs for the treatment of many chronic inflammatory conditions.

The use of tenoxicam to prevent symptoms of discomfort induced by vagotonia during uterus manipulation in cesarean sections

PURPOSE

Symptoms such as nausea, vomiting, tightness of the chest, bradycardia, and shoulder or abdominal discomfort, caused by vagotonia occurring during uterus manipulation, have concerned healthcare professionals for some time. Patients sometimes report these symptoms when undergoing spinal anesthesia for cesarean sections (CSs). We designed a prospective, double-blind study to investigate the effectiveness of tenoxicam in preventing these symptoms of discomfort.

METHODS

A total of 105 American Society of Anesthesiologists (ASA) class I-II nulliparous pregnant women, who were scheduled for a CS, were enrolled into this prospective, double-blind study. Spinal anesthesia was conducted to reach a peak dermatome level of no more than T3. The 100 patients were randomly divided into 2 groups having completed study course: Group T (N = 50) received a 20 mg dose of tenoxicam in 5 mL of normal saline (NS) immediately after skin incision and Group N (N = 50) only received 5 mL NS. The incidence and severity of the symptoms experienced by the patients were recorded by a nurse anesthetist who was blinded to the injection regimen the patients were receiving. A chi-square test was used for statistical analysis t test and P < .05 was defined as significant.

RESULTS

The incidence and degree of severity of nausea and vomiting were same in both the groups. The incidence and degree of severity of bradycardia, nausea, vomiting, tightness of the chest, shoulder discomfort, and abdominal discomfort were lower in Group T than in Group N.

CONCLUSION

Tenoxicam might theoretically block the parasympathetic vagus pathway and decrease the visceral pain or visceral-specific symptoms, alleviating the symptoms caused by vagotonia. However, the prophylactic effect of tenoxicam in reducing the incidence and severity of nausea and vomiting was not statistically significant. This could be because nausea and vomiting are not solely caused by vagotonia, but also by other mechanisms.

Room-Temperature Organocatalytic Cycloaddition of Azides with β-Keto Sulfones: Toward Sulfonyl-1,2,3-triazoles

Organocatalytic enamine-azide [3 + 2] cycloadditions between β-keto sulfones and aryl azides can be performed at room temperature in good to excellent yields of products in the presence of catalytic amounts of pyrrolidine (5 mol %). The proposed organocatalytic methodology was found to be applicable to β-keto arylsulfones containing a range of substituents. A wide variety of aryl azides also work. Basically, this constitutes a remarkably efficient protocol for the synthesis of novel 1,2,3-triazole compounds.

Regioselective synthesis and ab initio calculations of fused heterocycles thermally and under microwave irradiation

Pyrazolo[1,5-a]pyrimidine, triazolo[1,5-a]pyrimidine, and pyrimido[1,2-a]benzimidazole, pyrido[1,2-a]benzimidazole ring systems incorporating phenylsulfonyl moiety were synthesized via the reaction of 3-(N,N-dimethylamino)-1-(thiophen-2-yl)-2-(phenylsulfonyl)prop-2-en-1-one derivatives with the appropriate aminoazoles as 1,3-binucleophiles and 1H-benzimidazol-2-ylacetonitrile using conventional methods as well as microwave irradiation. The regioselectivity of the cyclocondensation reactions was confirmed both experimentally by alternative synthesis of reaction products and theoretically using ab initio quantum chemical calculations namely the Density Functional Theory (DFT). The theoretical work was carried out using the Becke, three parameter, Lee-Yang-Parr hybrid functional (B3LYP) combined with the 6-311++G(d,p) basis set. It was found that the final cyclocondensation reaction product depends mainly on the initial addition to the activated double bond by the nitrogen atom of the 1,3-binucleophiles that has the higher electron density.

Ultrasound-assisted synthesis of novel 1,2,3-triazoles coupled diaryl sulfone moieties by the CuAAC reaction, and biological evaluation of them as antioxidant and antimicrobial agents

A series of 1,2,3-triazoles coupled diaryl sulfone containing compounds were synthesized by the copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) reaction in benign solvents under ultrasound irradiation. In situ formation of azides from α-bromoketones together with the CuAAC reaction in one pot allowed safe handling and good availability of azides for the development of a small library of compounds. The sonication reduced reaction time and increased yields compared to otherwise same conditions. All synthesized compounds were evaluated for antibacterial, antifungal and antioxidant activities. Compounds 3b, 6b and 9e-9g were found to be the most potent antifungal agents with minimal inhibitory concentration (MIC) at 25 μg/mL; moreover other compounds revealed good to moderate antimicrobial activity. Compound 8e showed an excellent antioxidant activity using a DPPH free radical scavenging assay.

Development and Validation of HPTLC Method for Estimation of Tenoxicam and its Formulations

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and validated for the estimation of tenoxicam in the microemulsion gels. Tenoxicam was chromatographed on silica gel 60 F(254) TLC plate, as a stationary phase. The mobile phase was toluene: ethyl acetate: formic acid (6:4:0.3 v/v/v), which gave a dense and compact spot of tenoxicam with a R(f) value of 0.38±0.03. The quantification was carried out at 379 nm. The method was validated in terms of linearity, accuracy, precision and specificity. To justify the suitability, accuracy and precision of the proposed method, recovery studies were performed at three concentration levels. Statistical analysis proved that the proposed method is accurate and reproducible with linearity in the range of 100 to 400 ng. The limit of detection and limit of quantification for tenoxicam were 25 and 50 μg/spot, respectively. The proposed method can be employed for the routine analysis of tenoxicam as well as in pharmaceutical formulations.

Intravenous ibuprofen: the first injectable product for the treatment of pain and fever

This paper reviews the current data on the use of the first approved intravenous ibuprofen product for the management of post-operative pain and fever in the United States. The management of acute and post-operative pain and fever with nonsteroidal anti-inflammatory agents (NSAIDs) is well documented. A search in Medline and International Pharmaceutical Abstracts of articles until the end of November 2009 and references of all citations were conducted. Available manufacturer data on file were also analyzed for this report. Several randomized controlled studies have demonstrated the opioid-sparing and analgesic effects of 400 and 800 mg doses of intravenous ibuprofen in a series of post-operative patient populations. Two recent studies have also noted the improvement in fever curves in critically ill and burn patients. These data, along with pharmacokinetic and pharmacologic properties, are explored in this review, which addresses the clinical utility of a parenteral NSAID in a hospitalized patient for post-operative pain management and fever reduction. Further data on intravenous ibuprofen are needed to define long-term utilization, management of acute pain, and use in special populations.

The kinetics and molecular modeling of the complexation of tenoxicam with cyclodextrins in solution

The effect of cyclodextrins on photodegradation of tenoxicam (TEN) was studied at pH 4, 7 and 10. After 60 min of irradiation with UV light, the photodegradation was extensive. All cyclodextrins (alpha, beta, or gamma) stabilize TEN and reduce the rate of photodegradation. The largest effect of cyclodextrins is at pH 7. Molecular modeling results help to explain and manipulate the results. The results are discussed and compared with other results from previous studies.

Comparison of analgesic and anti-inflammatory efficacy of selective and non-selective cyclooxygenase-2 inhibitors in dental implant surgery

BACKGROUND

The analgesic and anti-inflammatory efficacy of tenoxicam and meloxicam were evaluated in this double-masked, randomized, prospective study by analyzing pain scores and the need for rescue-analgesic agents following dental implant surgery.

METHODS

One hundred patients, in whom 241 dental implants were placed, were divided into two groups. For 4 days beginning the day before surgery, the first group received meloxicam, 15 mg daily, and the second group received tenoxicam, 20 mg daily, followed by 1 hour preoperatively and for 2 days thereafter. Pain intensity was rated by the subjects based on a visual analog scale on the operation day and on the following 6 days. The patients were recommended to use a rescue analgesic if the pain score was > or =4. Postoperative complications, such as edema, hematoma, infection, severe pain, paresthesia, or gastrointestinal complaints, were also noted.

RESULTS

Statistical analysis revealed that 54% of patients in the tenoxicam group and 66% of patients in the meloxicam group used rescue analgesics on day 1. However, the difference between the groups was not significant (chi(2) = 1.05; P = 0.30). The relationship between the reduction of consumption and time was not significant in either group (Z = 0.84; P = 0.40). The relationship between the use of rescue analgesics and the number of implants placed was not significant. Among patients who reported postoperative complications, there was not a statistically significant difference between the groups (chi(2) = 0.04; P = 0.84).

CONCLUSION

Meloxicam and tenoxicam exhibited a similar analgesic and anti-inflammatory efficacy in the present investigation.

Pharmacokinetics of formulated tenoxicam transdermal delivery systems

To investigate the feasibility of developing a new tenoxicam transdermal delivery system (TDS), the pharmacokinetics of tenoxicam from various formulated TDS were evaluated and compared with values following oral administration of tenoxicam and with application of a piroxicam plaster (Trast) marketed in Korea. Based on previous in-vitro study results, a mixture of diethylene glycol monoethyl ether (DGME) and propylene glycol monolaurate (PGML) (40:60) was used as a vehicle, and caprylic acid, capric acid, lauric acid, oleic acid or linoleic acid (each at 3%) was added as an enhancer. Triethanolamine (5%) was used as a solubilizer, and Duro-Tak 87-2510 as a pressure-sensitive adhesive. Among these fatty acids used for the formulation of tenoxicam TDS, caprylic acid showed the greatest enhancing effect; the area under the plasma concentration-time profile (AUC) decreased in the order of caprylic acid>linoleic acid>or=oleic acid>lauric acid>capric acid. Compared with oral administration, maximum plasma concentration (Cmax) was significantly lower, and time to reach Cmax (Tmax) delayed with all formulated tenoxicam TDS. All formulated TDS resulted in a lower AUC than with the oral formulation, except for TDS containing caprylic acid, although the difference was statistically significant only with capric acid. The AUC for all the formulated tenoxicam TDS was significantly higher than that of the piroxicam plaster; TDS with caprylic acid increased AUC 8.53-fold compared with the piroxicam plaster. Even though the Tmax of tenoxicam TDS was not significantly different from that of the piroxicam plaster, Cmax was higher; formulations containing caprylic acid and linoleic acid increased Cmax by 7.39- and 8.76-fold, respectively. In conclusion, a formulation containing 1.5 mL DGME-PGML (40:60) with 3% caprylic acid and 5% triethanolamine mixed with 6 g Duro-Tak 87-2510 could be a good candidate for developing a new tenoxicam TDS to maintain a comparable extent of absorption to oral delivery while attaining a prolonged effect with fewer toxic events.

Comparison of intra-articular tenoxicam and oral tenoxicam for pain and physical functioning in osteoarthritis of the knee

This study was designed to compare efficacy of local administration of a nonsteroidal anti-inflammatory drug with systemic administration in patients with osteoarthritis (OA) of the knee. For this purpose, intra-articular tenoxicam and oral tenoxicam therapies were applied and the improvement in control of pain and physical functioning were evaluated. A total of 69 patients with OA of the knee were randomized into three groups. Patients in the first group (41 knees of 23 patients) were treated for 1-3 weeks with once weekly intra-articular injection of tenoxicam 20 mg. Patients in the second group (45 knees of 26 patients) received 20 mg/day tenoxicam orally for 3 weeks and only physical exercises were applied to the third group (32 knees of 20 patients). Physical examination of the knee joint, Western Ontario and McMaster Universities Index and the Lequesne Algofunctional Index were used as outcome measurements at baseline, and the 1st, 3rd and 6th months. More significant improvement in pain and disability parameters was observed in groups 1 and 2 than group 3 compared with baseline measures. Among the patients' responses a few of the differences were statistically significant, more in favour of tenoxicam, and tenoxicam seemed to be superior to exercise alone especially at the final evaluation. There was no significant difference between the oral and intra-articular tenoxicam treatment regimens. The results of this study showed that treatment of OA of the knee with intra-articular tenoxicam is as effective as that with oral tenoxicam. It can be thought that intra-articular administration can be preferred to oral therapy due to minimal possibility of systemic side effects.

Clinical tolerability of perioperative tenoxicam in 1001 patients – a prospective, controlled, double-blind, multi-centre study

We investigated adverse events (AEs) associated with perioperative tenoxicam in a double-blind, prospective, randomised study. Patients undergoing surgery, screened for contraindications to non-steroidal anti-inflammatory drug, received tenoxicam (n=750) on 2843 days or placebo (n=251) on 988 days, in courses of 1-12 days. There was no increase in the overall incidence of side effects with tenoxicam (33 vs 38% with placebo: P=0.15), or in major side effects (3.9 vs 2.0% with placebo: P=0.11). Of major side effects possibly or probably related to tenoxicam (2.1 vs 1.2% with placebo: P=0.26), all but one involved post-operative surgical site bleeding. However, in the subgroup of patients undergoing otorhinolaryngology surgery, surgical site bleeding occurred in 18 of 171 (10.5%) patients on tenoxicam and one of 57 (1.8%) on placebo (P=0.026); of these, nine in the tenoxicam group and 0 in the placebo were classified as major (P=0.07). One patient on tenoxicam experienced endoscopically proven duodenal ulceration with malaena. In conclusion, perioperative tenoxicam is well tolerated in comparison with placebo and the incidence of drug-related major AEs (other than post-operative bleeding) is no greater than 1 in 150 in low risk patients, but in patients undergoing otorhinolaryngological surgery there may be an increased risk of post-operative bleeding.

Differential analgesic effect of tenoxicam on the wound pain and uterine cramping pain after cesarean section

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used to enhance opioid analgesia in the acute pain service. The question, however, of whether NSAIDs produce a similar extent of potentiation among different types of pain, has not been thoroughly investigated.

MATERIALS AND METHODS

A randomized, placebo-controlled, double-blind study was performed to characterize the analgesic effect of tenoxicam, a long-acting NSAID, on resting wound pain, evoked wound pain, and uterine cramping pain after cesarean section. Saline (n = 48) or 20 mg tenoxicam (n = 45) was intravenously injected immediately after clamping the umbilical cord. All patients were instructed to obtain maximal postoperative analgesia by intravenous patient-controlled morphine. RESULTS Tenoxicam profoundly reduced the intensity of uterine cramping pain (3.6 [2.0-5.6] versus 5.5 [3.4-6.6]; p < 0.01) but had no additional effect on wound pain at rest, with movement, changing position, sitting, and walking. Intraoperative injection of 20 mg tenoxicam decreased the demand ratio for patient-controlled analgesia (PCA) and 24-hour morphine consumption by approximately 30%.

CONCLUSIONS

The data show that tenoxicam potentiates opioid analgesic effect on the somatic and visceral types of pain to different extents, and they suggest that intraoperative injection of 20 mg tenoxicam is sufficient to enhance intravenous PCA morphine on uterine cramping pain for the first 24 hours after cesarean section.

Spectrophotometric and potentiometric determination of piroxicam and tenoxicam in pharmaceutical preparations

Two simple and accurate methods are described for the determination of piroxicam and tenoxicam in their pharmaceutical preparations. The spectrophotometric method involves the oxidation of these drugs with potassium iodate in acid medium with the liberation of iodine and subsequent extraction with cyclohexane followed by measuring the absorbance at lambda=522 nm. Beer's law is obeyed in the concentration range of 0.05-1.1 and 0.05-0.6 mg x ml(-1) for piroxicam and tenoxicam, respectively. The apparent molar absorptivities of the resulting coloured products are found to be 2.7 x 10(3) and 2.5 x 10(3) l mol(-1) x cm(-1), whereas Sandell sensitivities are 0.012 and 0.013 g x cm(-2) for piroxicam and tenoxicam, respectively. The potentiometric method involves the direct titration of both drugs with N-bromosuccinimide in acid medium and the end point is determined potentiometrically using platinum indicator electrode. Piroxicam and tenoxicam can be determined quantitatively in the concentration range of 0.33-3.37 and 0.33-4.08 mg x ml(-1) for tenoxicam and piroxicam, respectively. The standard deviation and relative standard deviation values are found to be ranged from 0.05-0.07 and 0.37-0.98% and 0.025-0.078 and 0.25-1.2% for tenoxicam and piroxicam, respectively. The two methods are accurate within +/-1.0%. Optimum conditions affecting both methods are studied. The proposed methods are applied for the determination of the drugs in pure form and in commercial pharmaceutical preparations.

Tenoxicam 20 mg or 40 mg after thoracotomy: a prospective, randomized, double-blind, placebo-controlled study

Forty-five adults undergoing thoracotomy were randomized to receive placebo, tenoxicam 20 mg or tenoxicam 40 mg IV during chest wall closure. All patients received intraoperative fentanyl and intercostal blocks followed by morphine by patient-controlled analgesia. Patient numbers 13 to 45 also received thoracic epidural analgesia by continuous infusion of bupivacaine 0.125%, patient numbers 25 to 45 having fentanyl 2 microg/ml added to the epidural infusion. Efficacy parameters and adverse reactions were assessed over the first 24 hours postoperatively. On a 100 mm visual analogue scale, mean (SD) pain at rest (adjusted area under curve for hours 1 to 24) was 25.8 (12.5), 17.4 (14.8) and 16.5 (13.3) mm for groups receiving placebo, 20 mg and 40 mg tenoxicam, respectively (ANOVA: P<0.05). There were no significant differences between study groups postoperatively in pain on coughing, opioid consumption, blood gas measurements, nausea, vomiting, sedation, blood loss, haemoglobin or serum creatinine. One patient in each tenoxicam group reported epigastric pain, rated moderate. These data support the inclusion of tenoxicam 20 mg IV in the management of pain at rest for patients undergoing thoracotomy, but do not show additional benefit for a higher dose.

In vitro percutaneous absorption of tenoxicam from pressure-sensitive adhesive matrices across the hairless mouse skin

To investigate the feasibility of developing a new tenoxicam plaster, the effects of vehicles and penetration enhancers on the in vitro permeation of tenoxicam from a pressure-sensitive adhesive (PSA) matrices across the dorsal hairless mouse skin were studied. Vehicles employed in this study were propylene glycol (PG)-oleyl alcohol (OAI), PG-oleic acid (OA), and diethylene glycol monoethyl ether (DGME)-propylene glycol monolaurate (PGML) cosolvents with/without fatty acids. In this study, amines such as triethanolamine (TEA) and tromethamine (TM) were additionally used as a solubilizer. Among PSAs used, Duro-Tak 87-2510 showed much higher release rate than either Duro-Tak 87-2100 or Duro-Tak 87-2196. The relatively high flux rate was obtained with the formulation of DGME-PGML (40:60, v/v) with 3% OA and 5% TM, and the flux increased as a function of the dose; the initial flux up to 12 h was 4.98 +/- 1.38 microg/cm2/h at the tenoxicam dose of 50 mg/70 cm2. This flux was much higher than that of a commercial piroxicam patch (Trast) (1.24 +/- 0.73 microg/ cm2/hr) with almost only one-third that of the commercial patch. Therefore, these observations indicated that these composition of tenoxicam plaster may be practically applicable.

Tenoxicam i.v. in major gynaecological surgery--pharmacokinetic, pain relief and haematological effects

This study compared postoperative analgesic dispensation and measures relating to haemostasis following intravenous administration, in a randomized double-blinded manner, of either placebo or tenoxicam 20 mg to 30 women presenting for major gynaecological oncology surgery under a standardized, combined epidural/general anaesthetic technique. Pharmacokinetic disposition of tenoxicam in this patient cohort was also described. There was no objective or subjective alteration in haemostatic function or increase in blood loss, nor any deviation from the normal range of values. Postoperative analgesia during the first 48 hours was delivered to achieve a VAS endpoint of less than five on leg-raising, by a combination of a nurse-controlled low-dose background epidural infusion and patient-administered epidural bolus. Greater VAS variability was observed during the first four postoperative hours (P = 0.08). The tenoxicam group self-administered significantly fewer epidural bolus doses to maintain satisfactory analgesia compared with the placebo group during the first 24 hours (P = 0.004) and 48 hours (P = 0.01) postoperatively. Similar differences between the groups in the total dose of the epidural bupivacaine/fentanyl mixture delivered were described (4 h: P = 0.148; 24 h: P = 0.033; 48 h: P = 0.001) (Figure 2). Despite surgery, transfusion and the use of a renal protective fluid administration strategy, tenoxicam disposition was not greatly different from that widely described for healthy volunteers. There were no significant side-effects and no adverse events attributable to tenoxicam. In this small study we have shown that tenoxicam administered preoperatively reduced the epidural analgesic requirements during the first 48 hours following major gynaecological surgery. There was no clinical or pathological evidence of haematological impairment following a single i.v. administration of tenoxicam 20 mg.

Effect of tenoxicam on biochemical serum parameters of rats

Tenoxicam is a nonsteroidal analgesic of the oxicam group, which possesses both antipyretic and anti-inflammatory characteristics. The use of tenoxicam has recently increased and it is reported in the literature that treatments lasting between a few weeks to three months caused increases in serum alanine transferase (ALT), aspartate transferase (AST), gamma glutamyl transferase (GGT) and bilirubin in humans. Toxic dose treatments to rats caused alterations in renal parameters. To verify these observations, various biochemical parameters were examined following administration of nontoxic doses of tenoxicam to rats. Rats were divided into three groups. One group received tenoxicam 0.6 mg/kg/day; the second group received 1.2 mg/kg/day i.p. The control group received normal saline i.p. At the end of 15 days, blood samples from the animals' hearts were taken for routine biochemical tests. No statistically significant changes were observed in serum urea, uric acid, creatinine, electrolytes, ALT, AST, total protein, bilirubin or glucose levels between the treatment groups and control groups. Increases in GGT levels were found to be statistically significant in both of the treatment groups compared with the control group.

The analgesic efficacy of intravenous tenoxicam as an adjunct to patient-controlled analgesia in total abdominal hysterectomy

Nonsteroidal antiinflammatory drugs may reduce postoperative opioid consumption. We evaluated the analgesic efficacy of preoperatively administered tenoxicam in patients undergoing total abdominal hysterectomy. Patients were randomly assigned to receive IV either normal saline 4 mL (Group NS), tenoxicam 20 mg (Group T20), or tenoxicam 40 mg (Group T40) before the induction of anesthesia in a double-blinded fashion. Patient-controlled analgesia with fentanyl was used to assess postoperative opioid requirements. Pain was evaluated by visual analog scale at 2, 4, 6, 8, and 24 h postoperatively. Intraoperative bleeding as assessed by the surgeon, incidence of nausea, and gastrointestinal symptoms were recorded. No statistically significant difference was identified between groups in fentanyl consumption or pain scores. The incidence of nausea was similar in all groups. Two patients in Group T20 and two in Group T40 exhibited mild gastrointestinal symptoms. Intraoperative oozing was noted in two patients in Group T40. We conclude that patients undergoing total abdominal hysterectomy and receiving fentanyl via patient-controlled analgesia postoperatively do not benefit from tenoxicam pretreatment. On the contrary, the drug may be associated with an increased incidence of side effects.

IMPLICATIONS

The preoperative administration of 20 or 40 mg IV tenoxicam does not reduce fentanyl consumption via Patient-Controlled Analgesia, compared with placebo, after total abdominal hysterectomy. Additionally, tenoxicam may increase intraoperative bleeding and gastrointestinal side effects.

Flow-injection spectrophotometric methods for the determination of tenoxicam

Two sensitive and rapid flow-injection spectrophotometric methods are proposed for the determination of tenoxicam (TX). In the first method, a Fe(III)-tenoxicam complex is formed in a methanolic medium and the absorbance is measured at 540 nm, while the second method involves measurement of the absorbance at 355 nm of a solution containing the drug in hydrochloric acid medium. In both methods, the peak heights were proportional to tenoxicam concentration over the ranges 7.0-320 and 0.5-8.5 mg/l(-1), respectively. The methods have been applied to the routine determination of the drug in dosage forms.

Intravenous tenoxicam for analgesia following laparoscopic cholecystectomy

In a double-blind, placebo-controlled clinical trial (power of 80% to detect a 30% reduction in morphine consumption, P < 0.05) we have determined that intraoperative intravenous administration of tenoxicam 40 mg during laparoscopic cholecystectomy, when compared with placebo, was associated with a significant reduction in consumption of morphine at 6 hours and 12 hours (P < 0.05) but not at 24 hours, when assessed by patient-controlled analgesia. Furthermore there was a significantly greater requirement for "rescue" analgesia with intramuscular morphine in the placebo group during the period of the study. There was no difference between the groups in pain scores, either at rest or on movement, nor in the incidence of nausea and vomiting. No patient in either group suffered a respiratory rate less than 8/min or oversedation at any time, and there were no other adverse effects.

Pain control after dental surgery: a double-blind, randomised trial of lornoxicam versus morphine

Lornoxicam is a new non-steroidal anti-inflammatory drug of the oxicam class. This randomised, double-blind, placebo controlled trial compared the analgesic efficacy and tolerability of intramuscular (IM) injections of lornoxicam (4, 8, 16 and 20 mg) with morphine (10 and 20 mg) and placebo in 252 patients with mainly moderate to severe pain following surgical removal of an impacted mandibular third molar. Patients treated with lornoxicam or morphine experienced a significantly greater cumulative pain relief over the 4-h post-injection period (TOTPAR0-4) than placebo recipients. This effect appeared to be dose-dependent, with patients in the lornoxicam 4 mg or morphine 10 mg groups recording significantly lower TOTPAR0-4 scores than patients in the higher dosage groups of these drugs. No significant difference was detected between the morphine 20 mg group and the lornoxicam 8, 16 and 20 mg groups. Lornoxicam was well tolerated at all doses and was associated with a significantly lower incidence of adverse events than morphine 10 or 20 mg. Thus, the analgesic efficacy of IM lornoxicam at doses > or = 4 mg is superior to placebo, and doses > or = 8 mg are at least as effective as IM morphine 20 mg. Furthermore, lornoxicam possesses a more favourable tolerability profile than morphine and thus represents an attractive alternative for the treatment of moderate to severe acute pain.

Intra-articular use of tenoxicam in degenerative osteoarthritis of the knee joint

Twenty-eight patients, aged 58 years or more and with clinical and radiological evidence of degenerative osteoarthritis of the knee joint, were entered into an open 6-month pilot study. Patients received a single intra-articular injection of tenoxicam (20 mg) into the affected knee with rigid adherence to aseptic technique. Efficacy was assessed in 25 evaluable patients according to three parameters: pain, hydrarthrosis and range of joint movement. Ten days after injection, 40% of patients (10/25) had greatly improved pain, 24% (6/25) showed improvement, while 12% (3/25) experienced a worsening of their pain; the remaining patients (24%) showed no change. Ten days after injection, the percentage of patients with hydrarthrosis was reduced from 43% (12/28) to 20% (5/25). Range of movement of the affected joint 1 month after injection was increased in 60% (15/25) of patients, decreased in 16% (4/25), and unchanged in 24% (6/25). Two patients reported a slight allergic reaction to the injection; no other side-effects were detected. The results of this pilot study justify investigating the efficacy of intra-articular tenoxicam in controlled double-blind studies.

Bioequivalence of two oral dosage forms prepared from different polymorphic modifications of tenoxicam

The bioavailability of two pharmaceutical dosage forms formulated using different polymorphs of tenoxicam were compared. Serum levels of TNX were analysed using high performance liquid chromatography. The pharmacokinetic parameters were estimated following the oral administration of a single dose (20 mg) of the drug as two different polymorphs to 12 healthy volunteers. The differences between formulations were statistically insignificant.

A risk-benefit appraisal of injectable NSAIDs in the management of postoperative pain

The inadequacy of pain treatment has been demonstrated in many patient groups suffering from acute pain. The injectable nonsteroidal anti-inflammatory drugs (NSAIDs), including indomethacin, diclofenac, ketoprofen and ketorolac, provide relief from the pain associated with several different conditions. When administered alone or in combination with low doses of opioids, NSAIDs provide good pain relief after musculoskeletal trauma or operation. The main advantage of these agents is that they may form the first-line therapy for pain relief and thus decrease the need of opioids. This avoids respiratory depression which can be associated with opioids. In contrast to opioids, NSAIDs do not cause respiratory depression or have marked adverse effects on the central nervous system. However, they may be associated with adverse effects of the gastrointestinal tract, liver and kidneys, and may increase pre- and postoperative bleeding and cause allergic reactions. These effects are related to the ability of NSAIDs to inhibit prostaglandin synthesis. Use of NSAIDs has to be considered carefully in patients with asthma, allergy to aspirin and NSAIDs, atopy, peptic ulcer or bleeding disorders (such as abnormalities in blood coagulation or coagulation deficits). These considerations are especially important in elderly patients. Having taken these contraindications into account, many clinical studies have demonstrated that NSAIDs are at least as safe as opioids when administered in the short term. However, few studies have specifically monitored adverse effects or included patients over 65 to 70 years of age. In addition, patients with risk factors have often been excluded from the trials. Therefore, the risk-benefit ratio of NSAIDs requires further assessment.

Bioavailability of intramuscularly administered tenoxicam

Bioavailability of intramuscularly administered tenoxicam relative to single oral and relative to intravenous doses was determined in two separate randomized crossover studies. Twelve healthy volunteers (12 males, age 20-30 years) received a rapid intravenous injection and a single intramuscular dose and 12 other subjects (11 males, 1 female, age 21-25 years) a single oral and a single intramuscular dose of 20 mg of tenoxicam on two different occasions. The wash-out period between the two consecutive treatments was 4 weeks. Plasma concentrations after dosing were determined by a specific HPLC method. Differences in tenoxicam concentration-time profiles after the different routes of administration were limited to the first 2 h after dosing. Later, plasma concentrations were almost superimposable within and across the two studies. The extent of absorption of intramuscularly administered tenoxicam was complete (mean +/- CV per cent: F(abs) 0.99 +/- 20 per cent) with no difference between the two extravascular administrations (F(rel) 0.95 +/- 10 per cent, intramuscular vs oral). After intramuscular administration tenoxicam was more rapidly absorbed compared to the oral dose (Tmax 0.71 h +/- 80 per cent vs 1.4 h +/- 62 per cent; p > 0.05). Peak concentrations after oral and intramuscular administration (Cmax 2.5 mg l-1 +/- 19 per cent vs 2.7 mg l-1 +/- 14 per cent; p < 0.05) were very similar.

The effect of haemodialysis on the pharmacokinetics of tenoxicam in patients with end-stage renal disease

We have studied the pharmacokinetics of tenoxicam after single and multiple oral doses of 20 mg in five patients (2 men and 3 women) with end-stage renal disease undergoing haemodialysis. After a single dose, tenoxicam had a half-life (t1/2) of 33 h, an apparent clearance (CL.f-1) of 4.3 ml.min-1, and an apparent volume of distribution (Vz.f-1) of 11.81. The maximum tenoxicam concentration (Cmax) was 4.3 mg.l-1 at a median tmax of 1.7 h. There were no significant differences between the values calculated from the pre- or post-dialyser port plasma samples. Tenoxicam plasma concentrations measured during once daily dosing before and after haemodialysis showed that tenoxicam does not accumulate. Our findings suggest that dosage adjustment may not be required in patients with end-stage renal disease on haemodialysis taking tenoxicam.