What medicine to avoid when bleeding?

October 11, 2025 •

4 min read

NSAID-induced gastrointestinal (GI) toxicity is the 15th most common cause of death in the United States [1.3.4]. Understanding what medicine to avoid when bleeding or at risk of bleeding is crucial for personal health and safety [1.3.4].

Quick Summary

Certain medications and supplements can significantly increase bleeding risk by interfering with the body's clotting process. Key drug classes to be aware of include anticoagulants, antiplatelets, and nonsteroidal anti-inflammatory drugs (NSAIDs) [1.2.3, 1.4.1].

Key Points

Anticoagulants and Antiplatelets: Medications like warfarin, Eliquis, Xarelto, and Plavix are designed to prevent clots and significantly increase bleeding risk [1.2.3, 1.4.1].
NSAIDs are a Major Culprit: Common over-the-counter pain relievers like ibuprofen (Advil) and naproxen (Aleve) interfere with platelet function and increase the risk of gastrointestinal bleeding [1.2.2, 1.3.7].
Herbal Supplements Carry Risks: Natural supplements such as garlic, ginkgo biloba, ginger, turmeric, and high-dose Vitamin E can have blood-thinning effects [1.5.2, 1.5.6].
SSRIs Affect Platelets: Antidepressants like SSRIs can deplete serotonin in platelets, impairing their ability to aggregate and form clots, especially when combined with NSAIDs [1.7.3, 1.3.6].
Combination Therapy Increases Danger: Taking multiple medications that increase bleeding risk, such as an NSAID with an anticoagulant, can raise the risk of a major bleed by two- to four-fold [1.2.4].
Acetaminophen is a Safer Alternative: For pain relief, acetaminophen (Tylenol) is generally the safest choice for those on blood thinners as it doesn't typically interfere with blood clotting [1.6.1, 1.6.6].
Consult a Professional: Always talk to a doctor or pharmacist before starting any new medication or supplement, especially if you have a bleeding disorder or are taking blood thinners [1.2.2].

Understanding Your Bleeding Risk with Medications

When you have an injury, your body initiates a complex process called hemostasis to stop the bleeding. This involves blood cells called platelets clumping together to form a plug at the injury site, and a series of proteins known as clotting factors working together to create a strong fibrin clot [1.4.1, 1.4.7]. Several common medications, both prescription and over-the-counter, can interfere with these natural processes, leading to an increased risk of bleeding [1.2.3]. This risk is heightened for individuals with existing bleeding disorders, liver or kidney disease, or those scheduled for surgery [1.2.3, 1.3.3].

Prescription Medications That Increase Bleeding

Certain prescription drugs are designed to thin the blood, while for others, increased bleeding is a side effect. It is vital to be aware of these medications.

Anticoagulants

Often called "blood thinners," these medications work by slowing down the body's process of making clots. They act on various clotting factors in the blood [1.4.1, 1.2.6]. Doctors prescribe them to prevent dangerous clots in patients with conditions like atrial fibrillation, deep vein thrombosis (DVT), or after certain surgeries [1.4.5, 1.4.6].

Common Anticoagulants:

Warfarin (Coumadin, Jantoven) [1.2.3, 1.4.3]
Rivaroxaban (Xarelto) [1.2.3, 1.4.3]
Dabigatran (Pradaxa) [1.2.3, 1.4.3]
Apixaban (Eliquis) [1.2.3, 1.4.3]
Edoxaban (Savaysa) [1.2.3, 1.4.3]
Heparin and its derivatives (e.g., enoxaparin/Lovenox) [1.4.2, 1.4.3]

Antiplatelet Agents

Unlike anticoagulants that affect clotting factors, antiplatelet drugs prevent platelets from clumping together to form a clot [1.4.1]. Aspirin is the most well-known, but several powerful prescription versions exist, often used after a heart attack or stroke [1.4.1].

Common Antiplatelet Drugs:

Aspirin [1.2.3]
Clopidogrel (Plavix) [1.2.3]
Prasugrel (Effient) [1.2.3]
Ticagrelor (Brilinta) [1.2.3]

Selective Serotonin Reuptake Inhibitors (SSRIs)

Primarily used as antidepressants, SSRIs can also increase bleeding risk [1.2.4]. Platelets use serotonin to help with aggregation. By inhibiting the reuptake of serotonin, SSRIs can deplete the serotonin in platelets, impairing their ability to form a clot [1.7.3, 1.7.5]. The risk is significantly higher when SSRIs are taken in combination with NSAIDs or other blood thinners [1.3.6, 1.7.6].

Over-the-Counter (OTC) Medicines to Use with Caution

Many people don't realize that common pain relievers and cold remedies can pose a bleeding risk.

Nonsteroidal Anti-inflammatory Drugs (NSAIDs)

This is one of the most widely used classes of drugs for pain and inflammation [1.3.6]. NSAIDs work by blocking enzymes called COX-1 and COX-2. This action reduces pain but also inhibits platelet function, which is crucial for blood clotting [1.3.6, 1.3.7]. The risk of GI bleeding can increase three- to four-fold when using NSAIDs [1.3.7]. Combining NSAIDs with anticoagulants like warfarin can increase the risk of a major bleed by two- to four-fold [1.2.4].

Common NSAIDs:

Ibuprofen (Advil, Motrin) [1.2.2]
Naproxen Sodium (Aleve) [1.2.2]
Aspirin (Bayer, Excedrin) - Note: Aspirin is also an antiplatelet agent [1.2.2]
Diclofenac (Voltaren) - available as a topical gel as well [1.2.2]
Some products for heartburn or nausea, like Pepto Bismol and Alka Selzer, also contain salicylates similar to aspirin [1.2.2].

Herbal Supplements and Bleeding Risk

Natural does not always mean safe. Several herbal supplements have blood-thinning properties and can increase the risk of bleeding, especially if taken with anticoagulant or antiplatelet medications [1.5.3, 1.5.6].

Supplements to Be Aware Of:

Ginkgo Biloba: Can decrease coagulation and has been linked to bleeding events [1.5.2, 1.5.3].
Garlic: Can slow blood clotting [1.5.3, 1.5.6].
Ginger: High doses may affect clotting [1.5.3].
Turmeric (Curcumin): Has antiplatelet effects [1.5.2, 1.5.3].
Vitamin E: High doses can interfere with blood clotting, especially when taken with blood thinners [1.5.6].
Fish Oil (Omega-3 fatty acids): High doses can inhibit platelet aggregation [1.5.6].
Dong Quai: Has been shown to worsen bleeding in people taking warfarin [1.5.3].
Feverfew: Can affect platelets' ability to stick together [1.5.3].


Medication/Supplement Class	Mechanism of Action	Common Examples	Primary Use
Anticoagulants	Slows down the process of making clotting factors [1.4.1].	Warfarin, Rivaroxaban (Xarelto), Apixaban (Eliquis) [1.2.3].	Preventing blood clots (e.g., DVT, stroke in AFib) [1.4.5].
Antiplatelets	Prevents platelets from clumping together [1.4.1].	Aspirin, Clopidogrel (Plavix) [1.2.3].	Preventing heart attack and stroke [1.4.1].
NSAIDs	Inhibits COX enzymes, which also reduces platelet function [1.3.6].	Ibuprofen (Advil), Naproxen (Aleve) [1.2.2].	Pain relief, inflammation reduction [1.3.6].
Herbal Supplements	Varies; many have antiplatelet or anticoagulant properties [1.5.2, 1.5.3].	Garlic, Ginkgo Biloba, Vitamin E, Fish Oil [1.5.6].	Varies (dietary supplementation).

Safer Alternatives and When to See a Doctor

For pain relief, acetaminophen (Tylenol) is generally considered the safest option for people at risk of bleeding or on blood thinners, as it does not affect platelets or the stomach lining in the same way NSAIDs do [1.6.1, 1.6.6]. However, high doses can cause liver damage, so it's essential to follow dosing instructions [1.6.1].

Always consult your healthcare provider before starting any new medication or supplement, especially if you are taking a blood thinner [1.2.2]. You should contact your doctor if you experience any signs of unusual bleeding, such as:

Nosebleeds that won't stop
Blood in your urine (red or brown) or stool (red or black/tarry) [1.6.5]
Unusual or easy bruising [1.2.5]
Heavy or prolonged menstrual bleeding [1.6.5]
Severe headache or dizziness [1.6.5]

Conclusion

Awareness is the first step in medication safety. A wide range of drugs and supplements—from prescription anticoagulants like warfarin and Eliquis to common OTC pain relievers like ibuprofen and even natural supplements like garlic and ginkgo biloba—can interfere with your body's ability to stop bleeding [1.2.3, 1.5.3, 1.6.1]. The risk is compounded when these substances are taken together [1.2.4]. Always read labels, understand the potential side effects, and maintain an open dialogue with your healthcare provider about all medications and supplements you take to effectively manage your bleeding risk.

For more information on anticoagulation safety, you can visit the National Institutes of Health (NIH) bookshelf.

Frequently Asked Questions

Acetaminophen (Tylenol) is generally considered the safest over-the-counter pain reliever for individuals taking blood thinners like Eliquis or Xarelto because it does not interfere with platelet function or increase bleeding risk in the same way NSAIDs do [1.6.1, 1.6.6].

You should avoid taking NSAIDs like ibuprofen if you are at risk for bleeding, have a bleeding disorder, or have low platelets. These medications interfere with blood clotting and can be dangerous in these situations [1.2.2].

Yes, certain herbal supplements, including turmeric (curcumin) and high-dose fish oil, have antiplatelet or anticoagulant properties that can increase your risk of bleeding, especially if you are also taking a blood-thinning medication [1.5.2, 1.5.6].

Signs of internal bleeding can include severe or persistent headaches, dizziness, weakness, unusually easy bruising, nosebleeds, red or black tarry stools, and red or dark brown urine. If you experience these symptoms, you should seek medical attention [1.6.5, 1.3.7].

Anticoagulants, like warfarin, slow down the body's chemical process of making clots by acting on clotting factors. Antiplatelet drugs, like aspirin, prevent blood cells called platelets from clumping together to form an initial clot [1.4.1, 1.4.7].

While not primarily blood thinners, selective serotonin reuptake inhibitors (SSRIs) can increase bleeding risk. They interfere with serotonin uptake in platelets, which impairs the platelets' ability to aggregate and form a proper clot [1.7.3, 1.7.5].

Aspirin affects platelet function and can increase bleeding risk during surgery. Many surgeons recommend stopping aspirin and other NSAIDs for a period before a procedure, but you must consult with your doctor for specific instructions based on your health and the type of surgery [1.3.3].