Drug General Information (ID: DDIYSU6ANI)
Drug Name			Dipyridamole		Drug Info		Ginkgo biloba		Drug Info
Drug Type		Small molecule				Natural product
Therapeutic Class		Vasodilator Agents				Herbal Products

Mechanism of Dipyridamole-Ginkgo biloba Interaction (Severity Level: Moderate)
Increased risk of bleeding Click to Show/Hide Mechanism Graph
Drug Name		Dipyridamole				Ginkgo biloba
Mechanism		Risk of bleeding Antiplatelet				Risk of bleeding Antiplatelet effects
Key Mechanism Factor 1
		Factor Name		Bleeding
		Factor Description		Patients may be at risk for bleeding when the outcome of a disease or disease treatment confounds the standard mechanisms for maintaining hemostasis. Signs or symptoms of abnormal bleeding include: bleeding that takes a long time to stop (including nosebleeds, bleeding gums, bleeding from cuts and abrasions, and menstrual bleeding); severe unexplained bruising, or bruising that becomes larger; blood in the urine or stool, etc.
Mechanism Description		Increased risk of bleeding by the combination of Dipyridamole and Ginkgo biloba

Recommended Action
Management		Patients should consult a healthcare provider before taking any herbal or alternative medicine. In general, consumption of ginkgo should be avoided during use of coagulation-modifying agents and at least two weeks prior to surgery. In patients who have used this herb extensively prior to receiving anticoagulation, antiplatelet or thrombolytic therapy, the potential for an interaction should be considered. Close clinical and laboratory observation for hematologic complications is recommended. Patients should be advised to promptly report any signs of bleeding to their physician, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

References
1	Benjamin J, Muir T, Briggs K, Pentland B "A case of cerebral haemorrhage - can Ginkgo biloba be implicated?." Postgrad Med J 77 (2001): 112-3. [PMID: 11161079]
2	Chung KF, McCusker M, Page CP, Dent G, Guinot P, Barnes PJ "Effect of ginkgolide mixture (BN 52063) in antagonising skin and platelet responses to platelet acitivating factor in man." Lancet 1 (1987): 248-51. [PMID: 2880069]
3	Cupp MJ "Herbal remedies: adverse effects and drug interactions." Am Fam Physician 59 (1999): 1239-45. [PMID: 10088878]
4	Engelsen J, Nielsen JD, Winther K "Effect of coenzyme Q10 and Ginkgo biloba on warfarin dosage in stable, long-term warfarin treated outpatients. A randomised, double blind, placebo-crossover trial." Thromb Haemost 87 (2002): 1075-6. [PMID: 12083489]
5	Evans V "Herbs and the brain: friend or foe? The effects of ginkgo and garlic on warfarin use." J Neurosci Nurs 32 (2000): 229-32. [PMID: 10994537]
6	Fessenden JM, Wittenborn W, Clarke L "Gingko biloba: A case report of herbal medicine and bleeding postoperatively from a laparoscopic cholecystectomy." Am Surg 67 (2001): 33-5. [PMID: 11206893]
7	Fong KC, Kinnear PE "Retrobulbar haemorrhage associated with chronic Gingko biloba ingestion." Postgrad Med J 79 (2003): 531-2. [PMID: 13679551]
8	Fugh-Berman A "Herb-drug interactions." Lancet 355 (2000): 134-8. [PMID: 10675182]
9	Heck AM, DeWitt BA, Lukes AL "Potential interactions between alternative therapies and warfarin." Am J Health Syst Pharm 57 (2000): 1221-7 quiz 1228-30. [PMID: 10902065]
10	Izzo AA, Ernst E "Interactions between herbal medicines and prescribed drugs: a systematic review." Drugs 61 (2001): 2163-75. [PMID: 11772128]
11	Jayasekera N, Moghal A, Kashif F, Karalliedde L "Herbal medicines and postoperative haemorrhage." Anaesthesia 60 (2005): 725-6. [PMID: 15960738]
12	Jiang X, Williams KM, Liauw WS, et al. "Effect of ginkgo and ginger on the pharmacokinetics and pharmacodynamics of warfarin in healthy subjects." Br J Clin Pharmacol 59 (2005): 425-32. [PMID: 15801937]
13	Matthews MK Jr "Association of Ginko biloba with intracerebral hemorrhage." Neurology 50 (1998): 1933-4. [PMID: 9633781]
14	Miller LG "Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions." Arch Intern Med 158 (1998): 2200-11. [PMID: 9818800]
15	Rosenblatt M, Mindel J "Spontaneous hyphema associated with ingestion of Ginkgo biloba extract." N Engl J Med 336 (1997): 1108. [PMID: 9091822]
16	Rowin J, Lewis SL "Spontaneous bilateral subdural hematomas associated with chronic Gingko biloba ingestion." Neurology 46 (1996): 1775-6. [PMID: 8649594]
17	Sierpina VS, Wollschlaeger B, Blumenthal M "Ginkgo biloba." Am Fam Physician 68 (2003): 923-6. [PMID: 13678141]
18	Vaes LP, Chyka PA "Interactions of warfarin with garlic, ginger, or ginseng: nature of evidence." Ann Pharmacother 34 (2000): 1478-82. [PMID: 11144706]
19	Wolf HR "Does Ginkgo biloba special extract EGb 761 provide additional effects on coagulation and bleeding when added to acetylsalicylic acid 500 mg daily?" Drugs R D 7 (2006): 163-72. [PMID: 16752942]