Aggrenox (Dipyridamole/asa) is indicated to reduce the risk of stroke in patients who have had transient ischemia of the brain or completed ischemic stroke due to thrombosis.

The recommended dose of Aggrenox (Dipyridamole/asa) is one capsule given orally twice daily, one in the morning and one in the evening. Swallow capsules whole without chewing. Aggrenox (Dipyridamole/asa) can be administered with or without food.

25 mg/200 mg capsules with a red cap and an ivory-colored body, containing yellow extended-release pellets incorporating dipyridamole and a round white tablet incorporating immediate-release aspirin. The capsule body is imprinted in red with the Boehringer Ingelheim logo and with "01A".

In ESPS2 the incidence of gastrointestinal bleeding was 4.1% in the Aggrenox (Dipyridamole/asa) group, 2.2% in the extended-release dipyridamole group, 3.2% in the aspirin group, and 2.1% in the placebo groups.

Because Aggrenox (Dipyridamole/asa) contains aspirin, Aggrenox (Dipyridamole/asa) can cause fetal harm when administered to a pregnant woman. Maternal aspirin use during later stages of pregnancy may cause low birth weight, increased incidence for intracranial hemorrhage in premature infants, stillbirths and neonatal death. Because of the above and because of the known effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on the fetal cardiovascular system (closure of the ductus arteriosus), avoid Aggrenox (Dipyridamole/asa) in the third trimester of pregnancy [].

Aspirin has been shown to be teratogenic in rats (spina bifida, exencephaly, microphthalmia and coelosomia) and rabbits (congested fetuses, agenesis of skull and upper jaw, generalized edema with malformation of the head, and diaphanous skin) at oral doses of 330 mg/kg/day and 110 mg/kg/day, respectively. These doses, which also resulted in a high resorption rate in rats (63% of implantations versus 5% in controls), are, on a mg/m basis, about 66 and 44 times, respectively, the dose of aspirin contained in the maximum recommended daily human dose of Aggrenox (Dipyridamole/asa) . Reproduction studies with dipyridamole have been performed in mice, rabbits and rats at oral doses of up to 125 mg/kg, 40 mg/kg and 1000 mg/kg, respectively (about 1½, 2 and 25 times the maximum recommended daily human oral dose, respectively, on a mg/m basis) and have revealed no evidence of harm to the fetus due to dipyridamole. When 330 mg aspirin/kg/day was combined with 75 mg dipyridamole/kg/day in the rat, the resorption rate approached 100%, indicating potentiation of aspirin-related fetal toxicity. There are no adequate and well-controlled studies of the use of Aggrenox (Dipyridamole/asa) in pregnant women. If Aggrenox (Dipyridamole/asa) is used during pregnancy, or if the patient becomes pregnant while taking Aggrenox (Dipyridamole/asa) , inform the patient of the potential hazard to the fetus.

Dipyridamole has a vasodilatory effect. Chest pain may be precipitated or aggravated in patients with underlying coronary artery disease who are receiving dipyridamole.

For stroke or TIA patients for whom aspirin is indicated to prevent recurrent myocardial infarction (MI) or angina pectoris, the aspirin in this product may not provide adequate treatment for the cardiac indications.

The following adverse reactions are discussed elsewhere in the labeling:

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

The efficacy and safety of Aggrenox (Dipyridamole/asa) was established in the European Stroke Prevention Study-2 (ESPS2). ESPS2 was a double-blind, placebo controlled study that evaluated 6602 patients over the age of 18 years who had a previous ischemic stroke or transient ischemic attack within ninety days prior to entry. Patients were randomized to either Aggrenox (Dipyridamole/asa) , aspirin, ER-DP, or placebo []; primary endpoints included stroke (fatal or nonfatal) and death from all causes.

This 24-month, multicenter, double-blind, randomized study (ESPS2) was conducted to compare the efficacy and safety of Aggrenox (Dipyridamole/asa) with placebo, extended-release dipyridamole alone and aspirin alone. The study was conducted in a total of 6602 male and female patients who had experienced a previous ischemic stroke or transient ischemia of the brain within three months prior to randomization.

Table 1 presents the incidence of adverse events that occurred in 1% or more of patients treated with Aggrenox (Dipyridamole/asa) where the incidence was also greater than in those patients treated with placebo. There is no clear benefit of the dipyridamole/aspirin combination over aspirin with respect to safety.

Discontinuation due to adverse events in ESPS2 was 25% for Aggrenox (Dipyridamole/asa) , 25% for extended-release dipyridamole, 19% for aspirin, and 21% for placebo (refer to Table 2)

Headache was most notable in the first month of treatment.

The following is a list of additional adverse reactions that have been reported either in the literature or are from post-marketing spontaneous reports for either dipyridamole or aspirin. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to estimate reliably their frequency or establish a causal relationship to drug exposure. Decisions to include these reactions in labeling are typically based on one or more of the following factors: (1) seriousness of the reaction, (2) frequency of reporting, or (3) strength of causal connection to Aggrenox (Dipyridamole/asa) .

No pharmacokinetic drug-drug interaction studies were conducted with Aggrenox (Dipyridamole/asa) capsules. The following information was obtained from the literature.

Because of the dose ratio of dipyridamole to aspirin, overdosage of Aggrenox (Dipyridamole/asa) is likely to be dominated by signs and symptoms of dipyridamole overdose. In case of real or suspected overdose, seek medical attention or contact a Poison Control Center immediately. Careful medical management is essential.

Based upon the known hemodynamic effects of dipyridamole, symptoms such as warm feeling, flushes, sweating, restlessness, feeling of weakness and dizziness may occur. A drop in blood pressure and tachycardia might also be observed.

Salicylate toxicity may result from acute ingestion (overdose) or chronic intoxication. Severity of aspirin intoxication is determined by measuring the blood salicylate level. The early signs of salicylic overdose (salicylism), including tinnitus (ringing in the ears), occur at plasma concentrations approaching 200 µg/mL. In severe cases, hyperthermia and hypovolemia are the major immediate threats to life. Plasma concentrations of aspirin above 300 µg/mL are clearly toxic. Severe toxic effects are associated with levels above 400 µg/mL. A single lethal dose of aspirin in adults is not known with certainty but death may be expected at 30 g.

Treatment of overdose consists primarily of supporting vital functions, increasing drug elimination, and correcting acid-base disturbances. Consider gastric emptying and/or lavage as soon as possible after ingestion, even if the patient has vomited spontaneously. After lavage and/or emesis, administration of activated charcoal as a slurry may be beneficial if less than 3 hours have passed since ingestion. Charcoal absorption should not be employed prior to emesis and lavage. Follow acid base status closely with serial blood gas and serum pH measurements. Maintain fluid and electrolyte balance. Administer replacement fluid intravenously and augment with correction of acidosis. Treatment may require the use of a vasopressor. Infusion of glucose may be required to control hypoglycemia.

Administration of xanthine derivatives (e.g., aminophylline) may reverse the hemodynamic effects of dipyridamole overdose. Plasma electrolytes and pH should be monitored serially to promote alkaline diuresis of salicylate if renal function is normal. In patients with renal insufficiency or in cases of life-threatening intoxication, dialysis is usually required to treat salicylic overdose, however since dipyridamole is highly protein bound, dialysis is not likely to remove dipyridamole. Exchange transfusion may be indicated in infants and young children.

Aggrenox (Dipyridamole/asa) is a combination antiplatelet agent intended for oral administration. Each hard gelatin capsule contains 200 mg dipyridamole in an extended-release form and 25 mg aspirin, as an immediate-release sugar-coated tablet. In addition, each capsule contains the following inactive ingredients: acacia, aluminum stearate, colloidal silicon dioxide, corn starch, dimethicone, hypromellose, hypromellose phthalate, lactose monohydrate, methacrylic acid copolymer, microcrystalline cellulose, povidone, stearic acid, sucrose, talc, tartaric acid, titanium dioxide and triacetin.

Each capsule shell contains gelatin, red iron oxide and yellow iron oxide, titanium dioxide and water.

ESPS2 (European Stroke Prevention Study 2) was a double-blind, placebo-controlled, 24-month study in which 6602 patients over the age of 18 years had an ischemic stroke (76%) or transient ischemic attack (TIA, 24%) within three months prior to entry. Patients were enrolled in 13 European countries between February 1989 and May 1995 and were randomized to one of four treatment groups: Aggrenox (Dipyridamole/asa) (aspirin/extended-release dipyridamole) 25 mg/200 mg; extended-release dipyridamole (ER-DP) 200 mg alone; aspirin (ASA) 25 mg alone; or placebo. The mean age in this population was 66.7 years with 58% of them being males. Patients received one capsule twice daily (morning and evening). Efficacy assessments included analyses of stroke (fatal or nonfatal) and death (from all causes) as confirmed by a blinded morbidity and mortality assessment group. There were no differences with regard to efficacy based on age or gender; patients who were older had a trend towards more events.

Aggrenox (Dipyridamole/asa) capsules are available as a hard gelatin capsule, with a red cap and an ivory-colored body, 24.0 mm in length, containing yellow extended-release pellets incorporating dipyridamole and a round white tablet incorporating immediate-release aspirin. The capsule body is imprinted in red with the Boehringer Ingelheim logo and with "01A".

Aggrenox (Dipyridamole/asa) capsules are supplied in unit-of-use bottles of 60 capsules (NDC 21695-656-60).

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Inform patients that as with other antiplatelet agents, there is a general risk of bleeding including intracranial and gastrointestinal bleeding. Inform patients about the signs and symptoms of bleeding, including occult bleeding. Tell patients to notify their physician if they are prescribed any drug which may increase risk of bleeding.

Counsel patients who consume three or more alcoholic drinks daily about the bleeding risks involved with chronic, heavy alcohol use while taking aspirin.