DIPYRIDAMOLE Oral Suspension Ref.[7997] Active ingredients: Dipyridamole

Among other properties, dipyridamole acts as a vasodilator. It should be used with caution in patients with severe coronary artery disease, including unstable angina and/or recent myocardial infarction, left ventricular outflow obstruction or haemodynamic instability (e.g. decompensated heart failure).

Patients being treated with regular oral doses of Dipyridamole should not receive additional intravenous dipyridamole. Clinical experience suggests that patients being treated with oral dipyridamole who also require pharmacological stress testing with intravenous dipyridamole, should discontinue drugs containing oral dipyridamole for twenty-four hours prior to stress testing.

In patients with myasthenia gravis, readjustment of therapy may be necessary after changes in dipyridamole dosage (see section 4.5).

Dipyridamole should be used with caution in patients with coagulation disorders.

A small number of cases have been reported in which unconjugated dipyridamole was shown to be incorporated into gallstones to a variable extent (upto 70% by dry weight of stone). These patients were all elderly, had evidence of ascending cholangitis and had been treated with oral dipyridamole for a number of years. There is no evidence that dipyridamole was the initiating factor in causing gallstones to form in these patients. It is possible that bacterial deglucuronidation of conjugated dipyridamole in the bile may be the mechanism responsible for the presence of dipyridamole in gallstones.

Excipients in the formulation

Dipyridamole oral suspension contains liquid maltitol (E965). Patients with a rare hereditary problem of fructose intolerance should not take this medicine.

The medicine also contains methyl (E218) and propyl parahydroxybenzoates (E216) which may cause allergic reactions (possibly delayed).

This medicine also contains 545.20mg/5ml of propylene glycol (E1520) as an ingredient necessary for the medicine to work properly.

Dipyridamole increases plasma levels and cardiovascular effects of adenosine. Adjustment of adenosine dosage should be considered if use with dipyridamole is unavoidable.

There is evidence that the effects of aspirin and dipyridamole on platelet behaviour are additive.

The administration of antacids may reduce the efficacy of Dipyridamole. It is possible that Dipyridamole may enhance the effects of oral anti-coagulants.

When dipyridamole is used in combination with any substances impacting coagulation such as anticoagulants and antiplatelets the safety profile for these medications must be observed. Addition of dipyridamole to acetylsalicylic acid does not increase the incidence of bleeding events. When dipyridamole was administered concomitantly with warfarin, bleeding was no greater in frequency or severity than that observed when warfarin was administered alone.

Dipyridamole may increase the hypotensive effect of drugs which reduce blood pressure and may counteract the anticholinesterase effect of cholinesterase inhibitors thereby potentially aggravating myasthenia gravis.

Pregnancy

There is inadequate evidence of safety in human pregnancy, but Dipyridamole has been used for many years without apparent ill-consequence. Animal studies have shown no hazard. Medicines should not be used in pregnancy, especially the first trimester unless the expected benefit is thought to outweigh the possible risk to the foetus (please refer to section 5.3).

Lactation

Dipyridamole is excreted in breast milk at levels approximately 6% of the plasma concentration. Therefore Dipyridamole should only be used during lactation if considered essential by the physician.

Fertility

No studies on the effect on human fertility have been conducted with Dipyridamole. Non-clinical studies with dipyridamole did not indicate direct or indirect harmful effects with respect to fertility (please refer to section 5.3).

No studies on the effects on the ability to drive and use machines have been performed.

However, patients should be advised that they may experience undesirable effects such as dizziness during treatment with Dipyridamole. If patients experience dizziness they should avoid potentially hazardous tasks such as driving or operating machinery.

Adverse effects at therapeutic doses are usually mild and transient.

The following side effects have been reported, frequencies have been assigned based on a clinical trial (ESPS-2) in which 1654 patients received Dipyridamole alone.

Very common ≥1/10
Common ≥1/100 <1/10
Not known

Blood and lymphatic system disorders

Not known: Thrombocytopenia

Immune system disorders

Not known: Hypersensitivity, Angioedema

Nervous system disorders

Very common: Headache, Dizziness

Cardiac disorders

Common: Angina pectoris

Not known: Tachycardia

Vascular disorders

Not known: Hypotension, Hot flush

Respiratory, thoracic and mediastinal disorders

Not known: Bronchospasm

Gastrointestinal disorders

Very common: Diarrhoea, Nausea

Common: Vomiting

Skin and subcutaneous tissue disorders

Common: Rash

Not known: Urticaria

Musculoskeletal, connective tissue and bone disorders

Common: Myalgia

Injury, poisoning and procedural complications

Not known: Post procedural haemorrhage, operative haemorrhage

Dipyridamole has been shown to be incorporated into gallstones (please refer to section 4.4).

Reporting of suspected adverse reactions:

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme Website at: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

In the absence of compatibility studies, this medicinal product must not be mixed with other medicinal products.