Warfarin Dipyridamole

NSAIDs Aspirin Clopidogrel Dipyridamole Warfarin Heparin SSRIs... 

Tindurin - Pyrimethamine Tinidil Isosorbide dinitrate Tinigyn - Tinidazole Tinol - Dipyridamole Tinset - Oxatomide Tintorane Warfarin sodium Tinver - Salicylic acid... 

Do not combine with an antiplatelet agent o If patient experiences a systemic embolism while receiving warfarin and has a therapeutic INR, add aspirin 75-100 mg/d. For patients unable to take aspirin, then add dipyridamole 400 mg/d or clopidogel 75 mg/d. Immediate release dipyridamole needs an acidic gastric pH (<4) for adequate absorption... 

Adverse reactions at therapeutic doses are usually minimal and transient. With long-term use, initial side effects usually disappear. The following reactions were reported in 2 heart valve replacement trials comparing dipyridamole and warfarin therapy to either warfarin alone or warfarin and placebo dizziness, abdominal distress, headache, and rash. 

Drugs like salicylates, dipyridamole, phenylbutazone decrease the ability of platelets to aggregate, and thus impairing the haemostasis if warfarin induced bleeding occurs. 

Dipyridamole is a vasodilator that inhibits platelet function by inhibiting adenosine uptake and cGMP phosphodiesterase activity. Dipyridamole by itself has little or no beneficial effect. Therefore, therapeutic use of this agent is primarily in combination with aspirin to prevent cerebrovascular ischemia. It may also be used in combination with warfarin for primary prophylaxis of thromboemboli in patients with prosthetic heart valves. A combination of dipyridamole complexed with 25 mg of aspirin is now available for secondary prophylaxis of cerebrovascular disease. 

Dipyridamole (Persantine) is a vasodilator that, in combination with warfarin, inhibits embolization from prosthetic heart valves and, in combination with aspirin, reduces thrombosis in patients with thrombotic diseases. Dipyridamole by itself has little or no benefit in fact, in trials where a regimen of dipyridamole plus aspirin was compared with aspirin alone, dipyridamole provided no additional beneficial effect. Dipyridamole interferes with platelet function by increasing the cellular concentration of adenosine 3, 5 -monophosphate (cyclic AMP). This effect is mediated by inhibition of cyclic nucleotide phosphodiesterase and by blockade of uptake of adenosine, which acts at A2 receptors for adenosine to stimulate platelet adenylyl cyclase. The only current recommended use of dipyridamole is for primary prophylaxis of thromboemboli in patients with prosthetic heart valves the drug is given in combination with warfarin. 

Medications known to increase the risk of bleeding in cirrhotic patients include aspirin, clopidogrel, dipyridamole, corticosteroids, NSAIDs, heparin and warfarin. Mrs MW would need to be counselled about the risks associated with these medications and advised to always check with the pharmacist before buying any medications over the counter. 

ANTICOAGULANTS-ORAL DIPYRIDAMOLE Cases of mild bleeding when dipyridamole added to warfarin Antiplatelet effects of dipyridamole add to the anticoagulant effects Warn patients to report early signs of bleeding... 

In two of the five spontaneous bleeding episodes described in Heading 4, medications that can affect platelet function or prothrombin time (PT) (i.e., aspirin and warfarin) were involved. Because GB is known to be an inhibitor of PAF (41), in theory GB could interact with antiplatelet drugs (e.g., aspirin, nonsteroidal anti-inflammatory drugs, clopidogrel, ticlopidine, dipyridamole) or anticoagulants (e.g., warfarin, heparin). EGb 761 was shown to potentiate the antiplatelet effect of ticlopidine in rats (42). However, in two studies in humans, the coadministration of GB with warfarin had no effect on either international normalized ratio or warfarin metabolism (43,44). 

Ischemic stroke TPA, heparin, ASA, clopidogrel, ticlopidine, dipyridamole and aspirin, warfarin, surgery Neurological worsening, bieeding, PT/APTT, INR, CBC... 

While the effect of steroids has not been proven in adults, antiplatelet drugs, such as dipyridamole and aspirin, as well as warfarin, were found in randomized controlled trials to reduce proteinuria, but had no effect on GFR. ° However, an increased incidence of bleeding was observed in the treatment groups. Adult patients with idiopathic MPGN, heavy proteinuria, and/or impaired renal function should be given dipyridamole or aspirin. Unfortunately, no controlled... 

Zimmerman SW, Moorthy AV, DreherWH, etal. Prospective trial of warfarin and dipyridamole in patients with membranoproliferative glomerulonephritis. Am J Med 1983 75 920-927. 

Yoshikawa N, Ito H. Combined therapy with prednisolone, azathioprine, heparin-warfarin, and dipyridamole for paediatric patients with severe IgA nephropathy Is it relevant for adult patients Nephrol Dial Transplant 1999 14 1097-1099. 

There are no documented drug interactions, but garlic s antiplatelet effect might be dangerous in patients taking warfarin or antiplatelet agents such as aspirin, clopidogrel, ticlopidine, or dipyridamole. 

Dipyridamole was briefly mentioned in Chapter 10. In addition to vasodilator effects, the drug inhibits phosphodiesterase, thereby increasing intraplatelet c-AMP. Although these events do lead to decreased platelet aggregation, the drug s effectiveness clinically seems poor unless synergistically combined with either aspirin or warfarin. 

Also analyzed acebutolol, acepromazine, acetaminophen, acetazolamide, acetophenazine, albuterol, amitriptyline, amobarbital, amoxapine, antipsrrine, atenolol, atropine, azata-dine, baclofen, benzocaine, bromocriptine, brompheniramine, brotizolam, bupivacaine, buspirone, butabarbital, butalbital, caffeine, carbamazepine, cetirizine, chlorqyclizine, chlordiazepoxide, chlormezanone, chloroquine, chlorpheniramine, chlorpromazine, chlorpropamide, chlorprothixene, chlorthalidone, chlorzoxazone, cimetidine, cisapride, clomipramine, clonazepam, clonidine, clozapine, cocaine, codeine, colchicine, qyclizine, (yclo-benzaprine, dantrolene, desipramine, diazepam, diclofenac, diflunisal, diltiazem, diphenhydramine, diphenidol, dipheno late, dipyridamole, disopyramide, dobutamine, doxapram, doxepin, droperidol, encainide, ethidium bromide, ethopropazine, fenoprofen, fentanyl, flavoxate, fluoxetine, fluphenazine, flurazepam, flurbiprofen, fluvoxamine, fii-rosemide, glutethimide, glyburide, guaifenesin, haloperidol, homatropine, hydralazine, hydrochlorothiazide, hydrocodone, hydromorphone, hydro g chloroquine, hydroxyzine, ibuprofen, imipramine, indomethacin, ketoconazole, ketoprofen, ketorolac, labetalol, le-vorphanol, lidocaine, loratadine, lorazepam, lovastatin, loxapine, mazindol, mefenamic acid, meperidine, mephenytoin, mepivacaine, mesoridazine, metaproterenol, methadone, methdilazine, methocarbamol, methotrexate, methotrimeprazine, methoxamine, methyl-dopa, methylphenidate, metoclopramide, metolazone, metoprolol, metronidazole, midazolam, moclobemide, morphine, nadolol, nalbuphine, naloxone, naphazoline, naproxen, nifedipine, nizatidine, norepinephrine, nortriptyline, oxazepam, oxycodone, oxymetazo-line, paroxetine, pemoline, pentazocine, pentobarbital, pentoxifylline, perphenazine, pheniramine, phenobarbital, phenol, phenolphthalein, phentolamine, phenylbutazone, phenyltoloxamine, phenytoin, pimozide, pindolol, piroxicam, pramoxine, prazepam, prazosin, probenecid, procainamide, procaine, prochlorperazine, procyclidine, promazine, promethazine, propafenone, propantheline, propiomazine, propofol, propranolol, protriptyline, quazepam, quinidine, quinine, racemethorphan, ranitidine, remoxipride, risperidone, salicylic acid, scopolamine, secobarbital, sertraline, sotalol, spironolactone, sulfinpyrazone, sulindac, temazepam, terbutaline, terfenadine, tetracaine, theophylline, thiethyl-perazine, thiopental, thioridazine, thiothixene, timolol, tocainide, tolbutamide, tolmetin, trazodone, triamterene, triazolam, trifluoperazine, triflupromazine, trimeprazine, trimethoprim, trimipramine, verapamil, warfarin, xylometazoline, yohimbine, zopiclone... 

Interfering acenocoumarol, benazepril, chlordiazepoxide, clorazepate, dipyridamole, me-tapramine, mexiletine, nomifensine, oxprenolol, pipamperone, pyrimethamine, ticlopi-dine, trazodone, vincristine, vindesine, warfarin... 

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