Studies with atorvastatin,
lovastatin,
pravastatin, and
simvastatin suggest that they do not usually significantly alter the effects of warfarin, although cases of bleeding have been seen when these
statins were given with coumarins and fluindione.
It has been suggested that it would be prudent to monitor the early stages of concurrent use of
statins and anticoagulants in all patients, or if the dosage of statin is changed, being alert for the need to adjust the anticoagulant dosage. However, this interaction has only been clinically significant in a handful of patients, so monitoring every patient may be over-cautious.