Class: Hemorrheologic agent
- Tablets, controlled-release 400 mg
- Tablets, controlled-release 400 mg
Improves blood flow by decreasing blood viscosity.
Pentoxifylline is almost completely absorbed. Food delays absorption and increases C max by 28% and AUC by 13%. T max is 1 h (parent drug and metabolites).
Protein binding to erythrocyte membrane. Both parent drug and metabolites distribute into breast milk.
Extensive first-pass metabolism. Undergoes first-pass effect; in the liver, some metabolites are active with 5 to 8 times the plasma levels of the parent drug.
Urine (as metabolites), fecal (less than 4%). The plasma t ½ is 0.4 to 0.8 h (parent drug) and 1 to 1.6 h (metabolites).
2 to 4 wk (multiple doses).
Increases AUC and decreases elimination rate (60 to 68 yr of age).
Indications and Usage
Intermittent claudication on basis of chronic occlusive arterial disease of limbs.
Treatment of psychopathological symptoms in patients with cerebrovascular insufficiency; treatment of diabetic angiopathies and neuropathies, transient ischemic attacks, leg ulcers, sickle cell thalassemias, strokes, high-altitude sickness, asthenozoospermia, acute and chronic hearing disorders, severe idiopathic recurrent aphthous stomatitis, eye circulation disorders, and Raynaud phenomenon.
Intolerance to methylxanthines (eg, caffeine, theophylline); recent cerebral and/or retinal hemorrhage.
Dosage and AdministrationAdults
PO 400 mg 3 times daily with meals for at least 8 wk. If GI and CNS adverse reactions occur, decrease to 400 mg twice daily. If adverse reactions persist, discontinue.
Store at 59° to 86°F. Protect from light.
Small decreases in blood pressure possible in patients receiving pentoxifylline while using antihypertensive drugs. Monitor BP. If indicated, reduce dosage of the antihypertensive.Cimetidine
Effects of pentoxifylline may be increased.Theophylline
Coadministration with pentoxifylline leads to increased theophylline levels and possible toxicity in some patients. Monitor and adjust closely.Warfarin
Bleeding and prolonged PT possible.
Laboratory Test Interactions
None well documented.
Arrhythmia/palpitation, flushing (2%); angina/chest pain (1%); dyspnea, edema, hypotension, tachycardia (postmarketing).
Dizziness (12%); headache (6%); agitation/nervousness, insomnia (2%); drowsiness (1%); anxiety, aseptic meningitis, confusion, depression, malaise, seizures (postmarketing).
Brittle fingernails, pruritus, rash, urticaria (postmarketing).
Blurred vision (2%); conjunctivitis, earache, epistaxis, laryngitis, nasal congestion, scotoma, sore throat/swollen neck glands (postmarketing).
Nausea (29%); dyspepsia (10%); belching/flatus/bloating (9%); vomiting (5%); abdominal discomfort (4%); diarrhea (3%); anorexia, bad taste, constipation, dry mouth/thirst, excessive salivation (postmarketing).
Cholecystitis, hepatitis, increased liver enzymes, jaundice (postmarketing).
Aplastic anemia, decreased serum fibrinogen, leukemia, leukopenia, pancytopenia, purpura, thrombocytopenia (postmarketing).
Weight change (postmarketing).
Anaphylactoid reactions, angioedema, flu-like symptoms (postmarketing).
Periodically monitor patients with risk factors complicated by hemorrhage (eg, recent surgery, peptic ulceration, cerebral and retinal bleeding) for bleeding, including hematocrit and hemoglobin; patients receiving warfarin should have more frequent monitoring of PT.
Category C .
Excreted in breast milk.
Safety and efficacy not established.
Use with caution, usually starting at the low end of the dosage range, because of the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant diseases or other drug therapy.
Drug may accumulate, producing toxicity; lower dose may be necessary.
Periodically examine patients with risk of hemorrhage for bleeding.
Symptoms appear to be dose related. They usually occur 4 to 5 h after ingestion and last approximately 12 h. Symptoms include agitation, convulsions, fever, flushing, hypotension, loss of consciousness, and somnolence.
- Explain that improvement in symptoms may take 2 to 4 wk to notice and up to 8 wk for max relief.
- Explain importance of follow-up lab work for patients with high risk of bleeding or who are taking anticoagulants.
- In patients with occlusive peripheral vasospastic disorders, emphasize use of self-help measures to augment drug therapy (eg, exercise, weight control, no smoking).
- Review specifics of good foot care, including bathing of feet daily in lukewarm water and drying thoroughly, applying lanolin to feet after bathing, using lambswool between toes and feet, avoiding temperature extremes, wearing clean cotton socks daily.
- Instruct patient to report the following symptoms to health care provider: abnormal bleeding, chest pain, dizziness, excessive bruising, fainting.
- Advise patient that drug may cause dizziness, and to use caution while driving or performing other tasks requiring mental alertness.
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