Aggrenox is a prescription medication combining two antiplatelet agents—aspirin and dipyridamole—in an extended-release formulation specifically designed to reduce the risk of stroke in patients who have had transient ischemic attacks (TIAs) or completed ischemic strokes. This combination therapy works through complementary mechanisms to inhibit platelet aggregation more effectively than either component alone, offering a targeted approach to secondary stroke prevention. It is formulated to provide sustained pharmacological activity while minimizing peak-dose side effects, making it a cornerstone in neurology and vascular protection protocols. Clinical evidence supports its use as a first-line option for appropriate patient populations under specialist supervision.

Features

• Contains 25 mg aspirin and 200 mg extended-release dipyridamole per capsule
• Dual-mechanism antiplatelet action: cyclooxygenase-1 inhibition and phosphodiesterase inhibition
• Modified-release formulation for prolonged therapeutic effect
• Convenient twice-daily dosing regimen
• Manufactured under strict pharmaceutical quality standards

Benefits

• Significantly reduces the risk of recurrent ischemic stroke compared to aspirin monotherapy
• Provides synergistic platelet inhibition through two distinct pharmacological pathways
• Extended-release design helps maintain consistent plasma concentrations
• May offer superior vascular protection in high-risk patients with prior cerebrovascular events
• Supported by robust clinical trial data demonstrating efficacy and safety
• Convenient combination therapy improves adherence compared to multiple separate medications

Common use

Aggrenox is indicated to reduce the risk of stroke in patients who have had transient ischemic attacks (TIAs) or completed ischemic strokes due to thrombosis. It is specifically designed for secondary prevention in these patient populations and is not indicated for primary stroke prevention. The medication is typically prescribed by neurologists, cardiologists, or vascular specialists following a comprehensive assessment of the patient’s stroke risk factors, bleeding risk, and overall cardiovascular health. Treatment is generally long-term, often continuing indefinitely unless contraindications develop or significant adverse effects occur.

Dosage and direction

The recommended dosage is one capsule taken orally twice daily, approximately 12 hours apart, with a full glass of water. The capsules should be swallowed whole and not chewed, crushed, or opened. Administration with food may help reduce the incidence of gastrointestinal upset. Treatment should be initiated under medical supervision, typically starting the day after a qualifying ischemic event once intracranial hemorrhage has been ruled out. Dosage adjustments are not typically required for elderly patients, but careful monitoring is recommended. Patients should be advised to maintain consistent dosing timing to ensure optimal therapeutic coverage.

Precautions

Patients should be carefully evaluated for bleeding risk before initiation and periodically during treatment. Caution is advised in patients with history of peptic ulcer disease, hepatic impairment, renal impairment, or coagulation disorders. Regular monitoring of complete blood count and liver function tests is recommended. The medication may cause dizziness; patients should be cautioned about operating machinery or driving until they know how Aggrenox affects them. Use with caution in patients with coronary artery disease as dipyridamole may cause coronary steal phenomenon. Patients scheduled for surgical procedures should discuss appropriate management with their healthcare provider, as temporary discontinuation may be necessary.

Contraindications

Hypersensitivity to aspirin, dipyridamole, or any component of the formulation; asthma exacerbated by NSAIDs or salicylates; active pathological bleeding such as peptic ulcer disease or intracranial hemorrhage; severe hepatic impairment; severe renal failure (CrCl <30 mL/min); third trimester of pregnancy; and concomitant use with anticoagulants unless absolutely necessary and closely monitored. The medication is also contraindicated in children and adolescents with viral infections due to the risk of Reye’s syndrome associated with aspirin content.

Possible side effects

Common adverse reactions include headache (up to 39% of patients), dyspepsia (15-18%), abdominal pain (12-14%), nausea (11-13%), and diarrhea (8-10%). Less frequently reported effects include vomiting, dizziness, fatigue, and bleeding manifestations such as epistaxis or ecchymosis. Serious but rare side effects include gastrointestinal bleeding, intracranial hemorrhage, severe hypersensitivity reactions, hepatotoxicity, and thrombocytopenia. Most common side effects tend to diminish with continued therapy, particularly headaches which often resolve within the first week of treatment.

Drug interaction

Significant interactions occur with anticoagulants (warfarin, dabigatran, rivaroxaban, apixaban) increasing bleeding risk; other antiplatelet agents (clopidogrel, prasugrel, ticagrelor); NSAIDs increasing gastrointestinal bleeding risk; ACE inhibitors with reduced antihypertensive effect; methotrexate with increased toxicity; valproic acid with increased concentrations; and alcohol increasing gastric irritation. Dipyridamole may counteract the effects of cholinesterase inhibitors in myasthenia gravis. Adenosine should be used with caution during stress testing as dipyridamole potentiates its effects.

Missed dose

If a dose is missed, it should be taken as soon as remembered unless it is almost time for the next scheduled dose. In that case, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not take a double dose to make up for a missed one. Consistent adherence is important for maintaining antiplatelet protection, so patients should be educated about establishing routine dosing habits and using reminder systems if needed.

Overdose

Symptoms may include ringing in the ears, dizziness, nausea, vomiting, sweating, hyperventilation, restlessness, tachycardia, hypoglycemia, and bleeding manifestations. Severe overdose may lead to metabolic acidosis, hyperthermia, convulsions, coma, respiratory failure, and cardiovascular collapse. Management involves immediate medical attention, gastric lavage if presented early, activated charcoal administration, and supportive care including fluid replacement and correction of acid-base balance. Specific treatments may include vitamin K for coagulation abnormalities and alkaline diuresis to enhance salicylate elimination. Hemodialysis may be considered in severe cases.

Storage

Store at room temperature between 20°C to 25°C (68°F to 77°F) with excursions permitted between 15°C to 30°C (59°F to 86°F). Keep in the original container with the lid tightly closed to protect from moisture. Do not store in bathroom cabinets where humidity levels fluctuate. Keep out of reach of children and pets. Do not use beyond the expiration date printed on the packaging. Protect from excessive heat and light.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Treatment decisions should be made by qualified healthcare professionals based on individual patient circumstances. Patients should not alter their medication regimen without consulting their physician. The prescribing information provided here may not include all possible uses, directions, precautions, or interactions. Always refer to the official prescribing information and consult with a healthcare provider for complete information about this medication.

Reviews

Clinical studies demonstrate that Aggrenox reduces the relative risk of stroke by approximately 22-37% compared to aspirin alone in secondary prevention. The ESPRIT trial and ESPS-2 study provide robust evidence supporting its efficacy. Many neurologists report satisfactory outcomes in appropriate patients, noting particularly good results in those who tolerate the initial side effects. Patient experiences vary, with some reporting significant headache during the initial treatment period that typically subsides within the first week. Adherence rates are generally favorable due to the twice-daily dosing schedule compared to more frequent regimens. Long-term follow-up data support sustained effectiveness in stroke prevention when taken consistently as prescribed.