Dosing and uses of Feldene (piroxicam)
Adult dosage forms and strengths
capsule
- 10mg
- 20mg
Administration
Take with food or 8-12 oz water to avoid GI effects
Other Indications & Uses
20 mg PO qD or div BID; no more than 30-40 mg/d
Rheumatoid arthritis (incl. juvenile), osteoarthritis
Off-label: gout
Pediatric dosage forms and strengths
<12 years old: not recommended
Feldene (piroxicam) adverse (side) effects
1-10%
Indigestion (3.8-9.5% )
Upper respiratory infection (up to 8.3% )
Headache (2.4-8.3% )
Diarrhea (1.9-7.8% )
Nausea (2.4-7.2% )
Abdominal pain (1.9-4.7%)
Edema (0.6- 4.5% )
Anemia (up to 4.1% )
Dizziness (1.1-3.8% )
Constipation (0.8-2.6% )
Vomiting
Fever
Angina (<2% )
Congestive heart failure (<2% )
Hypertension (<2% )
Myocardial infarction (<2% )
Gastrointestinal hemorrhage (< 2% )
Gastrointestinal perforation, gastrointestinal ulcer (< 2% )
Inflammatory disorder of digestive tract (<2% )
Decreased platelet aggregation, purpuric disorder (<2% )
Hepatitis (<2% )
<1%
Erythema multiforme, erythroderma
Stevens-Johnson syndrome
Toxic epidermal necrolysis
Jaundice, liver failure
Anaphylactoid reaction
Immune hypersensitivity reaction
Cerebrovascular accident
Interstitial nephritis, renal failure
Asthma, bronchospasm
Angioedema
Tinnitus, hearing loss
Warnings
Black box warnings
Cardiovascular Risk
- NSAIDs may increase risk of serious cardiovascular thrombotic events, myocardial infarction (MI), & stroke, which can be fatal
- Risk may increase with duration of use
- Patients with risk factors for or existing cardiovascular disease may be at greater risk
- NSAIDs are contraindicated for perioperative pain in the setting of coronary artery bypass graft (CABG) surgery (increased risk of MI & stroke)
Gastrointestinal Risk
- NSAIDs increase risk of serious GI adverse events including bleeding, ulceration, & perforation of the stomach or intestines, which can be fatal
- GI adverse events may occur at any time during use & without warning symptoms
- Elderly patients are at greater risk for serious GI events
Contraindications
Absolute: ASA allergy
Relative: bleeding disorders, duodenal/gastric/peptic ulcer, stomatitis, SLE, ulcerative colitis, upper GI disease, late pregnancy (may cause premature closure of the ductus arteriosus)
Cautions
May increase risk of asthma (bronchial), cardiac disease, CHF, hepatic impairment, HTN, renal impairment
Long-term administration of NSAIDs may result in renal papillary necrosis and other renal injury; patients at greatest risk include the elderly, or those with impaired renal function, hypovolemia, heart failure, liver dysfunction, salt depletion, and individuals taking diuretics, ACE inhibitors, or ARBs
May cause serious gastrointestinal (GI) adverse events including inflammation, bleeding, ulceration, and perforation of the stomach, small intestine, or large intestine when used long term and can be fatal; administer lowest effective dose for short periods; use caution
NSAIDs including piroxicam can cause serious skin adverse events such as exfoliative dermatitis, Stevens-Johnson Syndrome (SJS), and toxic epidermal necrolysis (TEN), which can be fataL
Not for administration to patients that have experienced aspirin anaphylactoid reactions
Anemia reported in patients receiving NSAIDs, including piroxicam; may prolong bleeding time; monitor
NSAIDs may cause adverse eye reactions; consult ophthalmologist if symptoms occur
Based on mechanism of action, use of prostaglandin-mediated NSAIDs, including piroxicam, may delay or prevent rupture of ovarian follicles, which has been associated with reversible infertility in some women; women who have difficulties conceiving or who are undergoing investigation of infertility, withdrawal of NSAIDs, including piroxicam, should be considered
Heart Failure(HF) risk
- NSAIDS have the potential to trigger HF by prostaglandin inhibition that leads to sodium and water retention, increased systemic vascular resistance, and blunted response to diuretics
- NSAIDS should be avoided or withdrawn whenever possible
- AHA/ACC Heart Failure Guidelines; Circulation. 2016; 134
Pregnancy and lactation
Pregnancy category: C, D during third trimester of pregnancy (may cause premature closure of the ductus arteriosus)
The Quebec Pregnancy Registry identified 4705 women who had spontaneous abortions by 20 weeks' gestation; each case was matched to 10 control subjects (n=47,050) who had not had spontaneous abortions; exposure to nonaspirin NSAIDs during pregnancy was documented in approximately 7.5% of cases of spontaneous abortions and in approximately 2.6% of controls. (CMAJ, September 6, 2011; DOI:10.1503/cmaj.110454)
Lactation: excreted in breast milk; has adverse effect on the nursing infant
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Feldene (piroxicam)
Half-life:14-158 hr (average 50 hr)
Onset: 15-30 min (single 20 mg dose); 1 hr (multiple 20 mg doses)
Duration: 48-72 hr
Peak Plasma
Time: 3-5 hr (a single 20 mg dose)
Concentration: 1.5-2 mcg/mL (single 20 mg dose); 3-8 mcg/mL (multiple-dose of 20 mg daily)
Other Information
Protein Bound: 99.3% (with plasma concentrations 5-30 mcg/mL)
Vd: 0.12-0.14 L/kg
Metabolism: hydroxylation at the 5 position of the pyridyl side chain; conjugation by cyclodehydration, hydrolysis of: amide linkage, decarboxylation, ring contraction, N-demethylation
Metabolites: hydroxy, parent drug
Excretion: urine, feces
Enzymes inhibited: cyclooxygenase
Mechanism of action
Inhibits synthesis of prostaglandins in body tissues by inhibiting cyclooxygenase; at least 2 isoenzymes, cyclooxygenase-1 (COX-1) & -2 (COX-2)
