Is Tylenol A Blood Thinner? – Overview
A well-known brand name of acetaminophen is Tylenol; it is an over-the-counter (OTC) medicine that is often used for acute and chronic pain and to reduce fever. Tylenol is taken in combination with other pain relievers or analgesic drugs, namely, the Non-steroidal Anti-inflammatory drugs (NSAIDs) aspirin, ibuprofen, and naproxen sodium.
The patient taking a combination of analgesics with Tylenol may think of it as a blood thinner.
The mild blood-thinning properties of Aspirin are established in the medical literature. It is not uncommon for people to use these two painkillers to relieve bodily aches. However, Tylenol is not a blood thinner; people may use Aspirin because of its moderate blood-thinning activity.
When selecting between Tylenol and other analgesics, such as Aspirin, the patients should understand a few doubts and facts. The answer lies in our understanding of the two analgesics.
How does Tylenol exert its action?
Acetaminophen was synthesized for the first time in the mid-nineteenth century. Since then, it has become the most commonly used medication in the United States and Europe.
Although Tylenol demonstrates mild analgesic (pain-controlling) and antipyretic (fever-controlling) activities, it is largely devoid of anti-inflammatory activity. Even though its exact mode of action is unknown, it is likely suspected of exerting partial cyclooxygenase (COX) inhibitor activity in humans when consumed in doses typically used to treat mild pain and fever, such as 1g. At this dosage, platelet aggregation is not inhibited. However, the platelet-mediated inflammatory activity by the COX enzyme is reduced by about 40%. (1)
Epidemiological studies have also indicated that acetaminophen, a safe and effective drug, shows gastric adverse effects similar to conventional, non-specific NSAIDs at larger doses, 2000 mg and above.
In particular, Tylenol may prevent the nervous system’s production of prostaglandins. This distinguishes acetaminophen from NSAIDs such as ibuprofen, which also reduce tissue inflammation. Tylenol is also recommended by WHO in all three steps to pain management (analgesic ladder) to treat cancer pain. (2)
By contrast to Aspirin and other NSAIDs, it is important to note that Tylenol does not exert anti-inflammatory activity, being a mild inhibitor of COX. For this reason, Tylenol is not classified under the NSAID class of analgesic and is unsuitable for treating acute and chronic inflammatory pain conditions.
Other possible explanations for Tylenol’s pain modulation are the effects of Tylenol on the activity of endogenous neurotransmitter systems, such as the opioid and serotonergic systems. (3)
How is Tylenol different than other blood-thinning medicines?
Blood thinners or Anti-coagulants are oral medications that help a patient’s blood flow as fluidly as possible without clumping cells through a person’s vasculature. These drugs are used carefully to resolve clots in conditions like DVT, angina, stroke, and thrombosis. These drugs can help prevent the formation of blood clots and prevent the worsening of other dangerous conditions, such as heart attacks and strokes.
While Tylenol has no blood thinning properties, it can enhance the effects of other anti-coagulants like Warfarin. It is always advised to speak with your doctor to be sure your drugs won’t interact negatively if you have any questions regarding Tylenol, acetaminophen-containing drug combinations, or other medications. (4)
The platelets in the blood produce a substance called thromboxane A2, which is blocked by aspirin. When you get a paper cut or bleeding wound, platelets allow the blood to clot. However, when Aspirin blocks COX, it inhibits COX till the life of platelets, i.e., 3-7 days.
Hence, blood clotting is prevented, which is desirable in angina, stroke-related heart attacks, and micro-clot prevention. Aspirin in doses of 30mg-160mg/day can exert an anti-platelet effect. Other medications cannot counter aspirin’s effects. This can only be accomplished with time and the replenishment of new platelet stores. (5)
On the other hand, Tylenol is completely devoid of blood thinning properties as it only weakly exerts its action of COX enzyme. Even doses higher than 2g per day do not cause any significant increase in COX-blocking activity. This dose increase is contrarily limited by the side effect profile of Tylenol, gastric upset, and saturation of glutathione stores in the liver, which metabolizes Tylenol. (6)
It is important to know that aspirin may also be a minor active ingredient in other over-the-counter drugs like Alka-Seltzer and Excedrin, albeit it isn’t as widely advertised. You can avoid unintentionally consuming Aspirin in more than one method by carefully reading medicine labels and leaflets.
Why is Tylenol preferred for Pain?
Overall, Tylenol is safe and effective in relieving pain and fever. Tylenol is less likely to aggravate the stomach than aspirin and ibuprofen because experts believe it primarily exerts its effects on the central nervous system.
Aspirin as an analgesic is not widely used because of its gastric ulcer risk and effects on blood coagulation. However, Tylenol does not. This makes it safer for those who are already on anti-coagulant therapy or at risk for gastric or internal bleeding.
In most cases, Tylenol is the preferred pain treatment for pregnant women. Ibuprofen and other painkillers increase the risk of birth abnormalities and problems during pregnancy.
Where does Tylenol lag?
The maximum daily dose of Tylenol is 4g. This is reduced to 2g/day if the patient is liver compromised. If you take too much Tylenol, your liver may not function right, and liver enzymes can be elevated.
Tylenol-associated liver toxicity develops when doses >4g/day are accumulated in the liver. Your body converts Tylenol you ingest into a toxic by-product called N-acetyl-p-benzoquinone (NAPQI). This substance is normally metabolized by glutathione stores in the liver, which renders it non-toxic.
However, at higher doses (>7g/day) of Tylenol, the liver stores of glutathione are depleted, and no further metabolism of NAPQI takes place, due to which it accumulates in the liver and causes permanent harm to the liver tissue. Doses >10g/day are fatal for most individuals. (7)
Additionally, it is easy to overdose on acetaminophen unintentionally. Acetaminophen in Tylenol is a widely used active ingredient in pharmaceuticals. It is also employed to exert synergistic pain-relieving effects in combination with narcotic painkillers and pain relievers containing Caffeine and other stimulants.
You may consume the recommended dosage of Tylenol without realizing that other medications you are taking for pain management may also contain acetaminophen. Therefore, it is important to read medicine labels and package leaflets carefully. You should always inform your doctor of all the medications that you are taking or intend to take.
Tylenol and alcohol are filtered via the liver, which means that taking them together can make your liver more toxic. You should never take any medicines with alcohol.
Tylenol does not have the anti-inflammatory or blood-thinning qualities some might expect, similar to Aspirin.
Can Tylenol be taken with other blood thinners?
Your doctor might recommend using Tylenol for pain relief rather than Aspirin or ibuprofen if you are concomitantly taking blood thinners (Anti-coagulants) like Plavix, Eliquis, and Coumadin. Some patients may need additional blood thinner in addition to Aspirin, but this should be prescribed and guided by the practicing physician.
Paracetamol and oral anti-coagulants are frequently used in the co-treatment of arthritic patients. Taking Tylenol with Warfarin and other anti-coagulants may increase prothrombin time (one of the parameters that asses coagulation function, along with others like bleeding time). This Interaction can sometimes induce a life-threatening decrease in blood clotting.
If you have a history of liver function abnormality or liver disorder (hepatitis or cirrhosis), your doctor may not prescribe you Tylenol because of its liver toxicity. Your doctor might suggest using a painkiller that doesn’t potentially harm the liver when the liver is already impaired.
How can we reverse Tylenol toxicity?
Tylenol is one of the most frequent causes of medication-related poisoning and death. Tylenol poisoning can result from large-dose ingestion or from consuming low doses repeatedly. Overdosing or toxicity from acetaminophen can happen unintentionally or on purpose. The individual responses of each patient to Tylenol, as well as the observed increased toxicity with regular and higher dosing within the typical analgesic dose ranges, must be considered by prescribers.
The maximum daily dose of Tylenol is 4g/day for adults and 90 mg/kg for kids. Hepatotoxicity, or liver damage from chemicals, is more likely to occur in those with an underlying liver condition or who regularly drink alcohol. Following are the signs of toxicity,
- Jaundice (yellow appearance of skin and eyes)
- Gastric upset (Loss of appetite, Abdominal pain, Diarrhea, Nausea, Vomiting)
Supportive care includes intravenous fluids, anti-nausea medication, activated charcoal if taken within an hour of consumption, and antidote therapy, such as N-acetylcysteine (Acetadote® or Mucomyst®), the majority of patients survive acetaminophen toxicity.
Tylenol causes analgesia by acting on the spinal cord and the brain. Additionally, Tylenol may exert its pain-modulating effects through the nervous system, which is the most likely analgesic mechanism. Acetaminophen only weakly blocks COX activity in platelets. It does not have any blood-thinning activity; however, in combination with other blood thinners, it may cause profound blood thinning.
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