Bruising, with warfarin

PIRACETAM ANTICOAGULANTS - ORAL Case report of bleeding associated with t INR in a patient taking warfarin 1 month after starting piracetam Uncertain. Piracetam inhibits platelet aggregation but it is uncertain whether it has any effect on other aspects of the clotting cascade Warn patient to report easy bruising, etc. Monitor INR closely... 

May cause easy bruising and excessive bleeding from minor injuries. Reports of haemorrhage with concomitant use of warfarin and dan shen. INR may not always be altered. Case report with ginseng of normal coagulation studies during postoperative bleeding... 

More recent studies have used lower doses of aspirin. In one study in patients stabilised on warfarin with a target INR range of 3.0 to 4.5, the addition of aspirin 100 mg daily increased the risk of any bleeding by 55%, when compared with placebo (35% versus 22% per year), mainly due to an increase in minor haematuria, nosebleeds and bruising. However, the risk was more than offset by the overall reduction in mortality. ... 

An isolated report describes a very marked increase in the anticoagulant effects of warfarin, accompanied by bruising and bleeding, in a patient given itraconazole. Limited evidence su ests that itraconazole may increase the risk of over-anticoagulation with acenocoumarol or phenprocoumon. 

In one early report, a patient with a prosthetic heart valve and stabilised on warfarin developed blood blisters and bruised easily 12 days after starting miconazole gel 250 g four times a day for a presumed fungal mouth... 

A bulletin includes a brief mention of an inereased INR with vaginal bleeding and multiple bruising in a woman taking warfarin and gestri-none. ... 

Ten subjects stabilised on warfarin, with average prothrombin times of 18.8 seconds, had a mean reduction of 2.7 seconds in their prothrombin times after they took glutethimide 500 mg at bedtime for 4 weeks. Other studies have shown that up to 1 g of glutethimide daily for 1 to 3 weeks reduced the half-life of single-dose warfarin by between one-third to one-half Conversely, an unexplained report describes a paradoxical increase in prothrombin times and severe bruising in a patient stabilised on warfarin who took 3.5 g of glutethimide over a 5-day period. ... 

Warfarin. A man stabilised on warfarin had a fall in his prothrombin time from a range of 1.7 to 1.9 times his control value to 1.3 when he stopped taking piroxicam 20 mg daily. The prothrombin times rose and fell when he re-started and then stopped the piroxicam. Another patient taking warfarin had an increase in her prothrombin time (from a range of 16.5 to 18.1 seconds to 24.9 seconds) when piroxicam 20 mg daily was started, and a decrease when it was then stopped. " The INR of 2 Chinese patients rose to 4.5 and 4.2 after they were treated with piroxicam 20 mg daily and 0.5% topical piroxicam gel. One of them had bruises over the legs within 3 days."... 

However, a man stabilised on warfarin 5 mg daily developed widespread bruising and haematuria 2 weeks after starting to take omeprazole 20 mg daily. His prothrombin time was found to have risen to 48 seconds. He was later restabilised on omeprazole 20 mg daily with the warfarin dosage reduced to 2 mg daily. ... 

Methyl salicylate, in the form of gels, oil, or ointment applied to the skin, has been found to increase the effects of warfarin. Bleeding and bruising and/or raised INRs have been seen with both high " and low doses of methyl salicylate. One report described the possible additive effects of methyl salicylate oil (Kwan Loong Medicated Oil) and a decoction of Danshen (the root of Salvia miltiorrhiza) on the response to warfarin (see also Coumarins and related drugs + Herbal medicines Danshen (Salvia miltiorrhizay, p.415). A raised prothrombin time has also been reported with topical trolamine salicylate. ... 

Cannabinoids An interaction of warfarin with marijuana smoking has been reported in a 56-year-old man, in whom the INR rose from 1.8 to 12 and who had a constant nose-bleed and increased bruising [37 j. During the next 9 months, while he did not smoke marijuana, his INR was 1.08-4.40 and there were no bleeding complications. The authors suggested that marijuana may have inhibited the metabolism of warfarin and to a lesser extent displaced it from protein-binding sites. 

The symptom of vitamin K deficiency is increased risk of haemorrhage, ease of bruising, nose bleeding and blood in the urine. In infants, vitamin K deficiency may result in intracranial bleeding. Vitamin K deficiency is rare in adults although vitamin K status is assessed in the newborn and in the USA a routine injection of vitamin K is recommended for newborn babies, particularly premature babies where the vitamin K cycle may not be fidly established. Human breast milk is relatively low in vitamin K. There has been some controversy over whether or not childhood leukaemia can be linked to injection of newborns with vitamin K, but a large retrospective study fotmd no link. Certain dmgs such as warfarin, sulphona-mides and cephalosporins can affect vitamin K function. 

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