dipyridamole

Therapeutic Classification: antiplatelet agents, diagnostic agents (coronary vasodilators)

Pharmacologic Classification: platelet adhesion inhibitors

Indications ⬆ ⬇

REMS

As an alternative to exercise in myocardial perfusion scintigraphy (cardiac stress testing with radiotracer imaging).

Action ⬆ ⬇

Produces coronary vasodilation by inhibiting adenosine uptake.

Therapeutic effects:

In diagnostic thallium imaging, dipyridamole dilates normal coronary arteries, reducing flow to vessels that are narrowed and causing abnormal thallium distribution.

Pharmacokinetics ⬆ ⬇

Absorption: IV administration results in complete bioavailability.

Distribution: Widely distributed to tissues.

Metabolism/Excretion: Metabolized by the liver; excreted in the bile.

Half-Life: 10 hr.

Time/Action Profile ⬆ ⬇

(coronary vasodilation)

ROUTE	ONSET	PEAK	DURATION
IV	unknown	6.5 min	30 min

Contraind./Precautions ⬆ ⬇

Contraindicated in:

Hypersensitivity.

Use Cautiously in:

Hypotension;
Patients with platelet defects;
OB: Use during pregnancy only if potential maternal benefit justifies potential fetal risk;
Lactation: Use while breastfeeding only if potential maternal benefit justifies potential risk to infant;
Pedi: Children <6 yr (safety and effectiveness not established);

Adv. Reactions/Side Effects ⬆ ⬇

CV: hypotension, arrhythmias, flushing, MI

GI: nausea, diarrhea, GI upset, vomiting

Derm: rash

Neuro: dizziness, headache, syncope, transient cerebral ischemia, weakness

Resp: bronchospasm

Interactions ⬆ ⬇

Drug-drug:

Anticoagulants, thrombolytic agents, NSAIDs, cefotetan, or valproic acid may ↑ risk of bleeding.
↑risk of hypotension with alcohol.
Theophylline may ↓ effectiveness.

Route/Dosage ⬆ ⬇

IV (Adults ): 570 mcg/kg (max dose = 60 mg).

Availability ⬆ ⬇

(Generic available)

Solution for injection: 5 mg/mL
In combination with:
aspirin.

Assessment ⬆ ⬇

Monitor vital signs during and for 10–15 min after infusion. Obtain ECG in at least 1 lead. If severe hypotension occurs, place patient in a supine position with head tilting down. If severe chest pain or bronchospasm occurs, administer IV aminophylline 50–250 mg at a rate of 50–100 mg over 30–60 sec. If chest pain is unrelieved with aminophylline 250 mg, administer nitroglycerin SL. Treat as myocardial infarction if chest pain persists after nitroglycerin.

Lab Test Considerations:

Monitor bleeding time periodically during therapy.

Implementation ⬆ ⬇

IV Administration:

Intermittent Infusion: Diluent: Dilute in at least a 1:2 ratio of 0.45% NaCl, 0.9% NaCl, or D5W for a total volume of 20–50 mL. Undiluted dipyridamole may cause venous irritation.
Rate: Infuse over 4 min.

Patient/Family Teaching ⬆ ⬇

Explain purpose and side effects of medication. Advise patient to read Patient Information before starting therapy.
- Advise patient to consult health care professional before taking OTC medications concurrently with this medication.
- Advise patient to avoid the use of alcohol, as it may potentiate hypotensive effects. Tobacco products should also be avoided because nicotine causes vasoconstriction.
- Caution patient to change positions slowly to minimize orthostatic hypotension.
- Instruct patient to notify health care professional if unusual bleeding or bruising occurs. .
Rep: Advise women of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

section name header

Pronunciation ⬇

Classifications ⬆ ⬇