Oxaprozin

Molecular formula CisH sNOa Molecular weight 293.3 CAS Registry No. 21256-18-8 

Sample preparation 1 mL Plasma -I- 50 i.g ketoprofen + 200 p,L 1M HCl + 4-5 mL ethyl acetate, vortex for 1.5-2 min, centrifuge at 400 g for 10 min. Remove the organic layer and evaporate it to dryness under reduced pressure at 40-50°, reconstitute the residue in 200 (jlL MeOH, inject a 20 p,L aliquot. 

Mobile phase MeCN water 45 55 containing 2.5 mL/L acetic acid Flow rate 1 Ipjection volume 20 Detector UV 280 

Simultaneous acetaminophen, indomethacin, phenylbutazone, salicylic acid Noninterfering ibuprofen, piroxicam Interfering fenoprofen, flurbiprofen 

Matlis, R. Greenblatt, D.J. Rapid high-performance hquid chromatographic analysis of oxaprozin, a non-steroidal anti-inflammatory eigent. J.Chromatogr., 1984, 310, 445—449 

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The aluminum salts of dmgs are significant for two principal reasons reduction of dmg acidity in the stomach lining and reduction of undeskable flavor. Examples are the aluminum salts of glycine, acetylsahcyhc acid, ibuprofen, flurbiprofen, fenoprofen, flufenamic acid, oxaprozin, and a variety of aminobenzoic acid. Some of these compounds are Hsted in Table 2. 

Ibuprofen, naproxen, flurbiprofen, ketoprofen, fenoprofen, oxaprozin... 

OzTaetoprim, 302 Oxawniquine, 372 Oxantel, 303 Oxaprozin, 263 Oxazepam, 402 Oxazole synthesis, 263 Oxazolinone synthesis,... 

Category C (etodolac, ketorolac, mefenamic acid, meloxicam, nabumetone, oxaprozin, tolmetin, piroxicam, celecoxib). All NSAIDs are Category D if used in the third trimester or near delivery. Avoid during pregnancy, especially in the third trimester. 

Oxaprozin- False-positive urine immunoassay screening tests for benzodiazepines have been reported in patients taking oxaprozin. False-positive test results may be expected for several days following discontinuation of oxaprozin therapy. 

Drug/Food interactions Administration of tolmetin with milk decreased total tolmetin bioavailability by 16%. When tolmetin was taken immediately after a meal, peak plasma concentrations were reduced by 50%, while total bioavailability was again decreased by 16%. Peak concentration of etodolac is reduced by about 50% and the time to peak is increased by 1.4 to 3.8 hours following administration with food however, the extent of absorption is not affected. Food may reduce the rate of absorption of oxaprozin, but the extent is unchanged. 

CNS Dizziness (mefenamic acid, meloxicam, piroxicam, flurbiprofen, diciofenac, fenoprofen) headache (ketorolac, fenoprofen, indomethacin, diclofenac, flurbiprofen, meclofenamate, meloxicam, nabumetone, naproxen, tolmetin, ketoprofen, sulindac, celecoxib, mefenamic acid, piroxicam, ibuprofen) somnolence/drowsiness (fenoprofen, naproxen) asthenia (tolmetin, etodolac) malaise (etodolac) fatigue (indomethacin) insomnia (meloxicam). Dermatologic Rash/dermatitis, including maculopapular type (ibuprofen, sulindac, meclofenamate, oxaprozin, nabumetone, mefenamic acid, meloxicam) desquamation angioneurotic edema ecchymosis petechiae purpura alopecia pruritus (nabumetone, naproxen) eczema skin discoloration hyperpigmentation skin irritation peeling skin eruptions (naproxen). 

Nabumetone (Relafen) Naproxen (Aleve, Naprosyn, Anaprox) Oxaprozin (Daypro, Daypro ALTA) Piroxicam (Feldene) Sulindac (Clinoril) Tohnetin (Tolectin)... 

Apart from the salicylates NSAIDs include several classes of weak acids like propionic acid derivatives such as ibuprofen, carprofen, fenbufen, fenoprofen, flurbiprofen, ketorolac, loxoprofen, naproxen, oxaprozin, tiaprofenic acid and suprofen. Phenylbutazone is the most important representative of the pyrazolon derivatives which have a bad reputation for their risk of potentially fatal bone-marrow toxicity. To the acetic acid derivatives belong in-domethacin, diclofenac and sulindac. Sulindac is a pro-drug with less toxicity than indomethacin. The enolic acids include piroxicam, droxicam and tenoxicam. Meloxicam is an analog of piroxicam and has a high selectivity for COX-2. 

Oxaprozin (Daypro) has pharmacological properties that are similar to those of other propionic acid derivatives. However, it has a very long half-life (more than 40 hours) and therefore can be effective with once-a-day treatment. 

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