Pentoxitylline - (Trental)

pentoxitylline
(pen-tok-SIH-fi-lin)

Pharmacologic class: xanthine derivative
Therapeutic class: hemorrheologic
Pregnancy risk category: C

How supplied

Tablets (extended-release): 400 mg

Pharmacokinetics

Absorption: absorbed almost completely but slowed by food. Undergoes first-pass hepatic metabolism.
Distribution: bound by erythrocyte membrane.
Metabolism: metabolized extensively by erythrocytes and liver.
Excretion: excreted primarily in urine; less than 4% of drug is excreted in feces.
Half-1ife: about 30 to 45 minutes.

Route	Onset	Peak	Duration
P.O.	Unknown	3-4 hr	Unknown

Pharmacodynamics

Chemical effect: unknown; thought to increase RBC flexibility and lower blood viscosity.

Therapeutic effect: improves capillary blood flow.

Indications and dosage

Intermittent claudication caused by chronic occlusive vascular disease.

Adults: 400 mg P.O. t.i.d. with meals.

Adverse reactions

CNS: headache, dizziness.
GI: dyspepsia, nausea, vomiting.

Interactions

Drug-drug. Anticoagulants: increased anticoagulant effect. Adjust anticoagulant dosage as ordered.
Antihypertensives: increased hypotensive effect. Dosage adjustments may be necessary.

Drug-lifestyle. Smoking. vasoconstriction may result. Advise patient to avoid smoking, it may worsen his condition.

Contraindications and precautions

• Contraindicated in patients who are intolerant to methyixanthines, such as caffeine and theophylline, and in those with recent cerebral or retinal hemorrhage.
• Drug is not recommended for use in breast-feeding women.
• Use cautiously in pregnant women.
• Safety of drug has not been established in children.

NURSING CONSIDERATIONS

Assessment

• Assess patient’s condition before therapy and regularly thereafter.
• Be alert for adverse reactions and drug interactions.
• Be aware that elderly patients may be more sensitive to drug’s effects.
• Monitor patient’s hydration status if adverse GI reactions.
• Evaluate patient’s and family’s knowledge of drug therapy.

Nursing diagnoses

• Altered peripheral tissue perfusion related to condition
• Risk for fluid volume deficit related to drug-induced adverse GI reactions
• Knowledge deficit related to drug therapy

Planning and implementation

• Know that drug is useful in patients who are not good surgical candidates.
• Report adverse reactions to doctor; dosage may need to be reduced.

Patient teaching

• Advise patient to take with meals to minimize GI upset.
• Instruct patient to swallow drug whole, without breaking, crushing, or chewing.
• Tell patient to report adverse GI or CNS reactions.
• Advise patient to avoid smoking because nicotine causes vasoconstriction than can worsen his condition.
• Tell patient not to discontinue drug during first 8 weeks of therapy unless directed by doctor.

Evaluation

• Patient exhibits adequate peripheral tissue perfusion.
• Patient maintains adequate hydration throughout therapy.
• Patient and family state understanding of drug therapy.