Common side effects patients experience when taking blood thinners include dizziness, falls, headaches, stomachache and bleeding, according to the Agency for Healthcare Research and Quality. Patients experiencing any of these symptoms should call their doctor.
Bleeding is the most common side effect of blood thinners, says the Agency for Healthcare Research and Quality. The bleeding can show up as a bruise or an abnormally heavy menstrual period. Patients sometimes have bleeding around the gums or nose that doesn't stop quickly.
Other side effects caused by bleeding include stools that look like tar or include blood, states the Agency for Healthcare Research and Quality. Vomit or urine that is brown or bright red is also an indicator. Patients should also look for blood in phlegm resulting from coughing.
Patients taking blood thinners should take precautions to not get hurt and to seek medical attention if they do, warns the Agency for Healthcare Research and Quality. A bump on the head can result in dangerous bleeding in the skull. Patients should always use an electric razor and waxed dental floss to prevent cuts or abrasions.
It is important that patients take blood thinners as prescribed and ask their doctor before taking any over-the-counter medication or supplements, states the Agency for Healthcare Research and Quality. Some pain relievers as well as stomach and cold remedies can interfere with blood thinners.