Brands, Medical Use, Clinical Data
- Anti-inflammatory Agents
- Nonsteroidal Antiinflammatory Agents (NSAIDs)
Brands / Synonyms
Alvo; Daypro; Daypro Alta; Deflam; Oxaprozin; Oxaprozin [Usan:Ban:Inn:Jan]; Oxaprozina [Inn-Spanish]; Oxaprozine; Oxaprozine [Inn-French]; Oxaprozinum [Inn-Latin]; Voir
Used to relieve the inflammation, swelling, stiffness, and joint pain associated with rheumatoid arthritis and osteoarthritis.
Oxaprozin is a nonsteroidal antiinflammatory drug (NSAID) with analgesic and antipyretic properties. Oxaprozin is used to treat rheumatoid arthritis, osteoarthritis, dysmenorrhea, and to alleviate moderate pain.
Mechanism of Action
Antiinflammatory effects of Oxaprozin are believed to be due to inhibition of cylooxygenase in platelets which leads to the blockage of prostaglandin synthesis. Antipyretic effects may be due to action on the hypothalamus, resulting in an increased peripheral blood flow, vasodilation, and subsequent heat dissipation.
Oxaprozin is 95% absorbed after oral administration. Food may reduce the rate of absorption of oxaprozin, but the extent of absorption is unchanged. Antacids do not significantly affect the extent and rate of oxaprozin absorption.
Oral, mouse: LD50 = 1210 mg/kg; Oral, rabbit: LD50 = 172 mg/kg; Oral, rat: LD50 = 4470 mg/kg
Biotrnasformation / Drug Metabolism
Hepatic. Ester and ether glucuronide are the major conjugated metabolites of oxaprozin, and do not have significant pharmacologic activity.
Oxaprozin is contraindicated in patients with known hypersensitivity to oxaprozin. Oxaprozin should not be given to patients who have experienced asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs. Severe, rarely fatal, anaphylactic-like reactions to NSAIDs have been reported in such patients
Aspirin: Concomitant administration of Oxaprozin and aspirin is not recommended because oxaprozin displaces salicylates from plasma protein binding sites. Coadministration would be expected to increase the risk of salicylate toxicity.
Methotrexate: Coadministration of oxaprozin with methotrexate results in approximately a 36% reduction in apparent oral clearance of methotrexate. A reduction in methotrexate dosage may be considered due to the potential for increased methotrexate toxicity associated with the increased exposure.
ACE-inhibitors: Reports suggest that NSAIDs may diminish the antihypertensive effect of ACE-inhibitors. Oxaprozin has been shown to alter the pharmacokinetics of enalapril (significant decrease in dose-adjusted AUC0-24 and Cmax) and its active metabolite enalaprilat (significant increase in dose-adjusted AUC0-24). This interactionshould be given consideration in patients taking NSAIDs concomitantly with ACE-inhibitors.
Furosemide: Clinical studies, as well as post marketing observations, have shown that Oxaprozin can reduce the natriuretic effect of furosemide and thiazides in some patients. This response has been attributed to inhibition of renal prostaglandin synthesis. During concomitant therapy with NSAIDs, the patient should be observed closely for signs of renal failure (see PRECAUTIONS: Renal effects), as well as to assure diuretic efficacy.
Lithium: Coadministration of oxaprozin with lithium carbonate can cause an increase in serum lithium levels. Whenever oxaprozin is added to or removed from patients on lithium therapy, therapeutic drug monitoring of lithium levels should be performed.
Glyburide: While oxaprozin does alter the pharmacokinetics of glyburide, coadministration of oxaprozin to type II non-insulin dependent diabetic patients did not affect the area under the glucose concentration curve nor the magnitude or duration of control. However, it is advisable to monitor patientsŐ blood glucose in the beginning phase of glyburide and oxaprozin cotherapy.
Warfarin: The effects of warfarin and NSAIDs on gastrointestinal (GI) bleeding are synergistic, such that users of both drugs together have a risk of serious GI bleeding higher than that of users of either drug alone.
H2-receptor antagonists: The total body clearance of oxaprozin was reduced by 20% in subjects who concurrently received therapeutic doses of cimetidine or ranitidine; no other pharmacokinetic parameter was affected. A change of clearance of this magnitude lies within the range of normal variation and is unlikely to produce a clinically detectable difference in the outcome of therapy.
Beta-blockers: Subjects receiving 1200 mg Oxaprozin QD with 100 mg metoprolol bid exhibited statistically significant but transient increases in sitting and standing blood pressures after 14 days. Therefore, as with all NSAIDs, routine blood pressure monitoring should be considered in these patients when starting Oxaprozin therapy.
Other drugs: The coadministration of oxaprozin and antacids, acetaminophen, or conjugated estrogens resulted in no statistically significant changes in pharmacokinetic parameters in single- and/or multiple-dose studies. The interaction of oxaprozin with cardiac glycosides has not been studied.
Laboratory test interactions: False-positive urine immunoassay screening tests for benzodiazepines have been reported in patients taking Oxaprozin. This is due to lack of specificity of the screening tests. False-positive test results may be expected for several days following discontinuation of Oxaprozin therapy. Confirmatory tests, such as gas chromatography/mass spectrometry, will distinguish Oxaprozin from benzodiazepines.