dipyridamole

dipyridamole /di·py·rid·a·mole/ (di″pĭ-rid´ah-mōl) a platelet inhibitor and coronary vasodilator used to prevent thromboembolism associated with mechanical heart valves, to treat transient ischemic attacks, and as an adjunct in preventing myocardial reinfarction and in myocardial perfusion imaging.

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di·pyr·id·a·mole (d-pr-d-ml, -p-rd-)

n.

A drug that acts as a coronary vasodilator and is used in the long-term treatment of angina pectoris.

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dipyridamole

[dī′pirid′əmōl]

an antiplatelet agent.

indication When used in combination with coumarin anticoagulants, it is used to prevent postoperative thromboembolic complications of cardiac valve replacement.

contraindications It should be used with caution in hypotension.

adverse effects The adverse reactions are mild and transient, such as headache, dizziness, rash, nausea, and flushing.

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dipyridamole

(dīpir´idmol´),
n brand name: Persantine;
drug class: platelet aggregation inhibitor;
action: specific action unclear; inhibits ability of platelets to aggregate;
uses: prevention of transient ischemic attacks (TIA), inhibition of platelet aggregation to prevent myocardial reinfarction, prevention of coronary bypass graft occlusion with aspirin.

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dipyridamole

a coronary vasodilator with antiplatelet activity.

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dipyridamole

Apo-Dipyridamole FC (CA), Apo-Dipyridamole SC (CA), Novo-Dipiradol (CA), Persantin (UK), Persantine

Pharmacologic class: Platelet adhesion inhibitor

Therapeutic class: Antiplatelet agent, diagnostic agent (coronary vasodilator)

Pregnancy risk category B

Action

Unclear. May reduce platelet aggregation by inhibiting phosphodiesterase, adenosine uptake, or formation of thromboxane A₂. Produces vasodilation, thereby increasing coronary blood flow.

Availability

Injection: 10 mg/2 ml

Tablets: 25 mg, 50 mg, 75 mg, 100 mg

⊘Indications and dosages

➣ To prevent thromboembolism in patients with prosthetic heart valves

Adults: 75 to 100 mg P.O. q.i.d.

➣ Alternative to exercise in thallium myocardial perfusion imaging

Adults: 0.57 mg/kg I.V. infused over 4 minutes (0.142 mg/kg/minute). Maximum I.V. dosage is 60 mg.

Off-label uses

• Prevention of myocardial reinfarction (given with aspirin)
• Thrombotic thrombocytopenia purpura

Contraindications

• Hypersensitivity to drug

Precautions

Use cautiously in:
• hypotension, platelet defects
• pregnant or breastfeeding patients (safety not established)
• children younger than age 12 (safety not established).

Administration

• Know that drug is usually given with warfarin when used to prevent thromboembolism.
• Dilute I.V. solution with dextrose 5% in water or normal or half-normal saline solution, as directed.
• Give single I.V. dose over 4 minutes.
• When used as diagnostic agent, administer within 5 minutes of thallium injection.
• Give oral form with a full glass of water at least 1 hour before or 2 hours after meals. If gastric distress occurs, give with food.

Route	Onset	Peak	Duration
P.O.	Unknown	Unknown	Unknown
I.V.	Unknown	6.5 min	30 min

Adverse reactions

CNS: dizziness, headache, syncope; transient cerebral ischemia or weakness (with I.V. use)

CV: hypotension, arrhythmias, myocardial infarction (all with I.V. use)

GI: nausea, vomiting diarrhea, dyspepsia

Hematologic: prolonged bleeding time

Respiratory: bronchospasm (with I.V. use)

Skin: rash, flushing (with I.V. use)

Interactions

Drug-drug. Anticoagulants, cefamandole, cefoperazone, cefotetan, nonsteroidal anti-inflammatory drugs, plicamycin, sulfinpyrazone, thrombolytics, valproic acid: increased risk of bleeding

Aspirin: increased effect on platelet aggregation

Theophylline: negation of dipyridamole effects during thallium imaging

Drug-behaviors. Alcohol use: increased risk of hypotension

Patient monitoring

• Monitor for therapeutic efficacy, including improved exercise tolerance and decreased need for nitrates.
• Assess platelet and coagulation studies regularly.
• Monitor ECG and vital signs, especially blood pressure.

Patient teaching

• Advise patient to take drug 1 hour before or 2 hours after meals for best absorption.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and behaviors mentioned above.