Dipyridamole

 Risk Factor: C
 Class: CARDIOVASCULAR DRUGS / Vasodilators

Contents of this page:

Fetal Risk Summary
Breast Feeding Summary
References
Questions and Answers

Fetal Risk Summary

No reports linking the use of dipyridamole with congenital defects have been located. The drug has been used in pregnancy as a vasodilator and to prevent thrombus formation in patients with prosthetic heart valves (1,2,3,4,5,6,7 and 8). A single IV 30-mg dose of dipyridamole was shown to increase uterine perfusion in the 3rd trimester in 10 patients (9). In one pregnancy, a malformed infant was delivered, but the mother was also taking warfarin (1). The multiple defects in the infant were consistent with the fetal warfarin syndrome (see Coumarin Derivatives).

In a randomized, nonblinded study to prevent preeclampsia, 52 high-risk patients treated from the 13th week of gestation through delivery with daily doses of 300 mg of dipyridamole plus 150 mg of aspirin were compared to 50 high-risk controls (10). Four treated patients were excluded from analysis (spontaneous abortions before 16 weeks) vs. five controls (two lost to follow-up plus three spontaneous abortions). Hypertension occurred in 41 patients19 treated and 22 controls. The outcome of pregnancy was significantly better in treated patients in three areas: preeclampsia (none vs. 6,p<0.01), fetal and neonatal loss (none vs. 5,p<0.02), and severe intrauterine growth retardation (none vs. 4,p<0.05). No fetal malformations were observed in either group. Other reports and reviews have documented the benefits of this therapy, namely a reduction in the incidence of stillbirth, placental infarction, and intrauterine growth retardation (11,12,13,14,15,16 and 17).

Breast Feeding Summary

Dipyridamole is excreted into breast milk, but in levels too low to measure with current techniques (P.A. Bowers, personal communication, Boehringer Ingelheim Ltd, 1981). The manufacturer knows of no problems in breast-fed infants whose mothers were taking this drug (P.A. Bowers, personal communication, Boehringer Ingelheim Ltd, 1981).

References

1. Tejani N. Anticoagulant therapy with cardiac valve prosthesis during pregnancy. Obstet Gynecol 1973;42:78593.
2. Del Bosque MR. Dipiridamol and anticoagulants in the management of pregnant women with cardiac valvular prosthesis. Ginecol Obstet Mex 1973;33:1918.
3. Littler WA, Bonnar J, Redman CWG, Beilin LJ, Lee GD. Reduced pulmonary arterial compliance in hypertensive patients. Lancet 1973;1:12748.
4. Biale Y, Lewenthal H, Gueron M, Beu-Aderath N. Caesarean section in patient with mitral-valve prosthesis. Lancet 1977;1:907.
5. Taguchi K. Pregnancy in patients with a prosthetic heart valve. Surg Gynecol Obstet 1977;145:2068.
6. Ahmad R, Rajah SM, Mearns AJ, Deverall PB. Dipyridamole in successful management of pregnant women with prosthetic heart valve. Lancet 1976;2:14145.
7. Biale Y, Cantor A, Lewenthal H, Gueron M. The course of pregnancy in patients with artificial heart valves treated with dipyridamole. Int J Gynaecol Obstet 1980;18:12832.
8. Salazar E, Zajarias A, Gutierrez N, Iturbe I. The problem of cardiac valve prostheses, anticoagulants, and pregnancy. Circulation 1984;70(Suppl 1):I169I77.
9. Lauchkner W, Schwarz R, Retzke U. Cardiovascular action of dipyridamole in advanced pregnancy. Zentralbl Gynaekol 1981;103:2207.
10. Beaufils M, Uzan S, Donsimoni R, Colau JC. Prevention of pre-eclampsia by early antiplatelet therapy. Lancet 1985;1:8402.
11. Beaufils M, Uzan S, Donsimoni R, Colau JC. Prospective controlled study of early antiplatelet therapy in prevention of preeclampsia. Adv Nephrol 1986;15:8794.
12. Wallenburg HCS, Rotmans N. Prevention of recurrent idiopathic fetal growth retardation by low-dose aspirin and dipyridamole. Am J Obstet Gynecol 1987;157:12305.
13. Uzan S, Beaufils M, Bazin B, Danays T. Idiopathic recurrent fetal growth retardation and aspirin-dipyridamole therapy. Am J Obstet Gynecol 1989;160:763.
14. Wallenburg HCS, Rotmans N. Idiopathic recurrent fetal growth retardation and aspirin-dipyridamole therapy. Reply. Am J Obstet Gynecol 1989;160:7634.
15. Wallenburg HCS, Rotmans N. Prophylactic low-dose aspirin and dipyridamole in pregnancy. Lancet 1988;1:939.
16. Capetta P, Airoldi ML, Tasca A, Bertulessi C, Rossi E, Polvani F. Prevention of pre-eclampsia and placental insufficiency. Lancet 1986;1:919.
17. Romero R, Lockwood C, Oyarzun E, Hobbins JC. Toxemia: new concepts in an old disease. Semin Perinatol 1988;12:30223.
    
    

Questions and Answers

Dipyridamole:?, My mother in law has suffered a recent'mild' stroke. She has been prescribed dipyridamole. It seems to have produced side effects that have almost stopped her funtioning normally.
Is this a transitional effect? Should she persevere or consult her doctor? She is eighty five

Any time you have a medication that changes the behavior of the person taking it you need to call the doctor who prescribed that medication, make a list of anything else she is taking so that he has a full picture to make decisions with, he may need to change meds or the doseage.

How is Dipyridamole added to an intravenous bag?, I need to know how much is to be released through IV over the four hour period and proper medications it should be mixed with.

It's added by syringe and the rate/dose to be given is strictly by the doctors orders.

Why is DIPYRIDAMOLE used in opthalmology?, I know its an oral anticoagulant however i can't think of a reason why the opthalmologist at our clinic prescribes it?

I'm not very well-informed in opthalmology but since it is an anticoagulant, they probably prescribe it for the fear of coagulation in the eye (Eye blood vessels) and it acts to increase extracellular levels of adenosine which acts as an anti-inflammatory.

medication tablet called dipyridamole?,

http://www.nlm.nih.gov/medlineplus/drugi...

whot is dipyridamole?,

This medication is used along with other medications to reduce the risk of blood clots after heart valve replacement. It prevents excessive blood clotting. It is also used with aspirin to reduce the risk of death after a heart attack and to prevent another heart attack. You can read more about it here
http://health.yahoo.com/drug/d00213a1

what is dipyridamole?,

Dipyridamole is a drug that inhibits platelet aggregation and causes vasodilation.

* It inhibits the cellular reuptake of adenosine into platelets, red blood cells and endothelial cells leading to increased extracellular concentrations of adenosine.
* It also inhibits the enzyme adenosine deaminase which normally breaks down adenosine into inosine. This inhibition leads to further increased levels of extracellular adenosine.
* Dipyridamole also inhibits the enzyme phosphodiesterase which normally breaks down cAMP.
* Adenosine interacts with the adenosine receptors to cause increased cAMP via adenylate cyclase.
* cAMP impairs platelet aggregation and also causes arteriolar smooth muscle relaxation.

Modified release dipyridamole is used in conjunction with aspirin (under the trade name Aggrenox®) in the secondary prevention of stroke and transient ischemic attack. This practice is now confirmed by the ESPRIT trial.

Dipyridamole is also used in nuclear cardiac stress testing as a coronary vasodilator.

* Via the mechanisms mentioned above, it increases the local concentration of adenosine in the coronary circulation which causes vasodilation.
* Vasodilation of healthy arteries is physiologic, whereas diseased arteries actually experience a drop in blood flow via "steal" phenomena which can be detected by electrocardiogram and echocardiography when it causes ischemia.
* Flow heterogeneity (a necessary precursor to ischemia) can de detected with gamma-cameras and SPECT using nuclear imaging agents such as Thallium-201 and Tc99m-Sestamibi.