Quick Summary
Blood thinners are medications that prevent blood clots from forming or growing larger. They work by interfering with the body’s clotting process. Some common blood thinners include warfarin (Coumadin), heparin, enoxaparin (Lovenox), dabigatran (Pradaxa), rivaroxaban (Xarelto), and apixaban (Eliquis).
When you take a blood thinner, it makes your blood take longer to clot. This helps prevent dangerous clots from forming in your veins or arteries. However, it also increases your risk of bleeding. Some of the effects blood thinners can have on your body include:
- Increased risk of bleeding – This includes nosebleeds, bleeding gums, blood in urine or stool.
- Easy bruising – Blood thinners can cause you to bruise more easily from minor bumps or injuries.
- Heavier periods – Women may experience heavier menstrual periods while on blood thinners.
- Prolonged bleeding from cuts – Small cuts may bleed longer than normal.
- Internal bleeding – Serious internal bleeding can occur but is rare. Symptoms include dizziness, abdominal pain, vision changes.
- Reduced clotting of blood – Blood will take longer to clot so you may need to apply pressure to cuts for longer.
- Reactions from other medications – Blood thinners can interact with other drugs like NSAIDs, antibiotics, or herbal supplements.
Monitoring your dosage and being aware of side effects is important when taking blood thinners. Always talk to your doctor about any concerns.
How Do Blood Thinners Work?
Blood thinners work by inhibiting the body’s clotting mechanisms. Clots normally form to stop bleeding at the site of an injury. The clotting process has several steps that involve platelets and proteins called clotting factors.
Blood thinners interfere with certain clotting factors or platelets to prevent clots from growing too large or forming unnecessarily inside blood vessels. This helps maintain proper blood flow and reduces the risk of events like stroke, heart attack, pulmonary embolism.
There are different types of blood thinners that work in slightly different ways:
- Warfarin (Coumadin) – Warfarin blocks the activity of vitamin K, which is needed to activate clotting factors.
- Heparin – Heparin enhances the activity of antithrombin, a natural anticoagulant protein in the body.
- Enoxaparin (Lovenox) – A low-molecular-weight heparin that also activates antithrombin.
- Dabigatran (Pradaxa) – Directly inhibits thrombin, a key clotting factor that converts fibrinogen to fibrin.
- Rivaroxaban (Xarelto) – Directly inhibits Factor Xa, another clotting factor.
- Apixaban (Eliquis) – Also directly inhibits Factor Xa.
So in summary, blood thinners slow down the clotting cascade in order to prevent abnormal clot formation. The level of anticoagulation needs to be carefully balanced since too much increases bleeding risk.
Increased Risk of Bleeding
One of the main side effects of blood thinners is an increased risk of bleeding. This risk needs to be carefully managed.
When blood takes longer to clot, you may experience:
- Prolonged nosebleeds
- Bleeding gums when brushing teeth
- Blood in urine or stool
- Heavy menstrual bleeding in women
- Easy bruising from minor bumps or injuries
- Prolonged bleeding from small cuts
- Serious internal bleeding (rare)
Women may have heavier periods while on blood thinners. Tampons should be avoided and pads changed frequently.
For nosebleeds, apply pressure and ice packs. Seek medical help if bleeding persists.
With cuts or injuries, apply firm pressure for 5-10 minutes and elevate the area if possible. Cuts may require bandages for longer than normal.
Serious internal bleeding is possible with blood thinners but quite rare. Internal bleeding can occur in the brain, digestive tract, throat, or muscles. Seek emergency care if you experience symptoms like:
- Dizziness or weakness
- Severe headache
- Vision changes
- Severe abdominal pain
- Vomiting blood or passing blood
- Coughing up blood
- Unexplained swelling or pain
- Unusually heavy vaginal bleeding
To reduce bleeding risks:
- Take blood thinners exactly as prescribed
- Use a soft toothbrush and waxed dental floss
- Shave with an electric razor instead of razor blades
- Avoid contact sports that may cause injury
- Prevent falls in the home with good lighting and rails
- Tell all doctors you see that you take blood thinners
Easy Bruising
Another common effect of blood thinners is easy bruising. With slower clotting time, even small knocks can cause bruises to appear. Bruises happen when blood leaks into the surrounding tissues under the skin.
On blood thinners, you may notice bruises popping up on your arms and legs for no apparent reason. Bruises can be larger than normal. It takes longer for them to change color and fade away.
To reduce bruising:
- Wear protective gear if playing contact sports
- Cover up with clothing to avoid bumps
- Use heating pads or hot compresses to help bruises heal
- Avoid taking other medications like aspirin or NSAIDs
- Eat foods rich in vitamin K like leafy greens
See your doctor if you experience excessive bruising, especially large bruises for no known reason. This can indicate a medication issue or more serious bleeding problem.
Heavier Menstrual Periods
Women taking blood thinners often experience heavier menstrual periods. This is because the uterine lining takes longer to stop bleeding each month.
Periods may last longer by a few days. There is likely to be more blood flow with possible passage of clots. Tampons should not be used since they can cause abrasions – stick with pads only. The pads will need to be changed more frequently than normal.
To manage heavy periods on blood thinners:
- Use extra-absorbent menstrual pads
- Change pads every 2-3 hours or more often if needed
- Avoid using tampons
- Take an iron supplement if periods lead to anemia
- Use a heating pad for cramps
- Get medical help for periods lasting over 1 week
Let your doctor know if periods become excessively heavy. They may adjust your medication dose accordingly. Birth control pills can sometimes help lighten bleeding.
Prolonged Bleeding from Cuts
When you take blood thinners and get a minor cut, the blood will take longer to clot and stop flowing.
Small cuts may bleed for 5 to 10 minutes longer than they normally would. The anticoagulant effect prevents a clot from forming quickly to seal off the injured blood vessel.
To stop bleeding from cuts:
- Apply firm, steady pressure to the cut using a clean bandage or cloth.
- Hold pressure for 5-10 minutes without peeking.
- Elevate the cut area above the level of your heart if you can.
- Once bleeding stops, clean the cut with soap and water.
- Bandage the cut using antibiotic ointment and change the bandage daily.
- Contact your doctor if bleeding persists longer than 10 minutes.
For more serious cuts that require stitches, your doctor may use special agents to help control bleeding. Let all healthcare providers know you take blood thinners before any procedures.
Reduced Clotting of Blood
Blood thinners slow down the body’s natural clotting mechanisms. Your blood will take longer to form a clot compared to someone not taking these medications.
When a blood vessel is injured, platelets normally rush to the site and clump together to plug the hole, stopping blood loss. Clotting factors activate to form fibrin threads that strengthen the platelet plug.
On blood thinners, this process is impeded. Platelets are less able to aggregate. It takes longer for clots to fully form.
You can see the anticoagulant effect in the time it takes your blood to clot. A common test is the PT/INR blood test, which measures your “prothrombin time” – how long it takes your blood plasma to clot.
Your doctor will monitor this with blood tests to make sure your levels are within the desired range for your condition. Therapeutic ranges differ based on the blood thinner medication.
While reduced clotting prevents dangerous clots, it does come with an increased risk of bleeding as a side effect. This risk needs to be carefully balanced and monitored.
Reactions with Other Medications
Blood thinners can sometimes interact with other medications, causing enhanced or reduced anticoagulant effects.
Drugs that may react with blood thinners include:
- Antiplatelet agents like aspirin, clopidogrel (Plavix), ticagrelor (Brilinta)
- Nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen (Advil, Motrin)
- Some antibiotics
- Antifungal medications
- Heart medications like amiodarone (Cordarone)
- Seizure medications like phenytoin (Dilantin)
- Antidepressants like fluoxetine (Prozac)
- Some herbal supplements like garlic, ginger, ginkgo, ginseng
These interactions can increase anticoagulant effects, raising bleeding risks. On the other hand, some drugs may reduce blood thinner efficacy.
Always let your doctor know about any new medications you are prescribed or over-the-counter drugs/supplements you take. Your blood thinner dosage may need adjustment to maintain proper anticoagulation.
Conclusion
Blood thinners provide important protection against dangerous blood clots in those at risk. However, they come with side effects like increased bleeding.
Common effects include easier bruising, heavy periods, prolonged bleeding from cuts, and a reduced clotting ability in your blood. Serious bleeding is possible but rare.
To stay safe on blood thinners:
- Take them exactly as prescribed
- Get regular monitoring tests
- Avoid medications that interact
- Prevent falls or injuries to lower bleeding risks
- Seek medical help if you have signs of serious bleeding
Blood thinners need to be closely managed under medical supervision. Being aware of the side effects can help minimize risks. Talk to your doctor if you have any concerns about how blood thinners are affecting you.