pentoxifylline

Increases the flexibility of RBCs by increasing levels of cyclic adenosine monophosphate (cAMP).
Decreases blood viscosity by inhibiting platelet aggregation and decreasing fibrinogen.

Therapeutic effects:

Increased blood flow.

Pharmacokinetics ⬆ ⬇

Absorption: Well absorbed following oral administration; food ↑ absorption.

Distribution: Bound to RBC membrane. Enters breast milk.

Metabolism/Excretion: Metabolized by RBCs and the liver.

Half-Life: 25–50 min.

Time/Action Profile ⬆ ⬇

(improvement in blood flow)

ROUTE	ONSET	PEAK	DURATION
PO	2–4 wk	8 wk	8 hr

Contraind./Precautions ⬆ ⬇

Contraindicated in:

Hypersensitivity;
Intolerance to other xanthine derivatives (caffeine and theophylline).

Use Cautiously in:

Coronary artery or cerebrovascular disease;
Renal impairment (dose ↓ may be needed);
Mild-to-moderate hepatic impairment
Geri: risk of adverse reactions;
OB: Safety not established.

Adv. Reactions/Side Effects ⬆ ⬇

CV: angina, arrhythmias, edema, flushing, hypotension

EENT: blurred vision

GI: abdominal discomfort, belching, bloating, diarrhea, dyspepsia, flatus, nausea, vomiting

Neuro: agitation, dizziness, drowsiness, headache, insomnia, nervousness, tremor

Resp: dyspnea

Misc: ANAPHYLAXIS

Interactions ⬆ ⬇

Drug-drug:

Additive hypotension may occur with nitrates.
May ↑ the risk of bleeding with warfarin, heparin, aspirin, NSAIDs, cefotetan, valproic acid, clopidogrel, eptifibatide, tirofiban, or thrombolytic agents.
May ↑ the risk of theophylline toxicity.
Smoking may ↓ the effects.
Strong CYP1A2 inhibitors, including ciprofloxacin and fluvoxamine may ↑ levels
Cimetidine may ↑ levels.

Drug-Natural Products:

↑bleeding risk with anise, arnica, asafoetida, chamomile, clove, dong quai, fenugreek, feverfew, garlic, ginger, ginkgo, Panax ginseng, licorice.

Route/Dosage ⬆ ⬇

PO (Adults ): 400 mg 3 times daily; if GI or CNS side effects occur, ↓ dose to 400 mg twice daily.

Renal Impairment

PO (Adults ): CCr <30 mL/min: 400 mg once daily.

Availability ⬆ ⬇

(Generic available)

Extended-release tablets: 400 mg

Assessment ⬆ ⬇

Assess patient for intermittent claudication prior to and periodically throughout therapy.
Monitor BP periodically in patients on concurrent antihypertensive therapy.
Monitor for signs and symptoms of anaphylaxis (wheezing, peri-oral or lingual edema, hemodynamic instability, rash, urticaria) during therapy.

Implementation ⬆ ⬇

PO: Administer with meals to minimize GI irritation. DNC: Swallowed whole; do not crush, break, or chew.
- If GI and CNS side effects occur, decrease dose to twice daily. Discontinue if side effects persist.

Patient/Family Teaching ⬆ ⬇

Instruct patient to take medication as directed. Take missed doses as soon as remembered unless almost time for next dose. Consult health care professional before discontinuing medication, because several wk of therapy may be required before effects are seen.
May cause dizziness and blurred vision. Caution patient to avoid driving and other activities requiring alertness until response to medication is known.
Advise patient to avoid smoking, because nicotine constricts blood vessels.
Instruct patient to notify health care professional if nausea, vomiting, GI upset, drowsiness, dizziness, or headache persists.
Rep: Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected and to avoid breastfeeding during therapy.

Evaluation/Desired Outcomes ⬆ ⬇

Relief from cramping in calf muscles, buttocks, thighs, and feet during exercise.
- Improvement in walking endurance. Therapeutic effects may be seen in 2–4 wk, but therapy should be continued for ≥8 wk.

section name header

Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇

Action ⬆ ⬇