What Is Tylenol (acetaminophen) and what Is it used for?
Tylenol (acetaminophen) is an analgesic (pain reliever) and antipyretic (fever reducer) to relieve fever as well as aches and pains associated with many conditions. Tylenol relieves pain in mild arthritis but has no effect on the underlying inflammation, redness, and swelling of the joint. If the pain is not due to inflammation, Tylenol is as effective as aspirin. Tylenol is, however, as effective as the non-steroidal anti-inflammatory drug (NSAID) ibuprofen (Motrin) in relieving pain due to osteoarthritis of the knee. When used appropriately, side effects with Tylenol are not common.
Other important side effects of Tylenol include
- hypersensitivity reactions,
- serious skin reactions,
- kidney damage,
- anemia, and
- low platelets in the blood (thrombocytopenia).
Chronic alcohol use may increase the risk of stomach bleeding. The most serious side effect of Tylenol is liver damage due to large doses, chronic use or concomitant use with alcohol or other drugs that also damage the liver. Other serious side effects of Tylenol include
- bleeding in the intestines and stomach,
- Stevens-Johnson syndrome,
- kidney damage, and
- reduced white blood cell counts.
Tylenol is often used during pregnancy for short-term treatment of fever and minor pain during pregnancy. Tylenol is excreted in breast milk in small quantities, however, use by nursing mothers appears to be safe.
What are the important side effects of Tylenol (acetaminophen)?
When used appropriately, side effects with acetaminophen are not common.
Other important side effects include:
- Hypersensitivity reactions
- Serious skin reactions
- Kidney damage
- Reduced number of platelets in the blood (thrombocytopenia)
Chronic alcohol use may also increase the risk of stomach bleeding. The most serious side effect is liver damage due to large doses, chronic use or concomitant use with alcohol or other drugs that also damage the liver.
Other serious side effects that have been reported include bleeding in the intestines and stomach, angioedema, Stevens-Johnson syndrome, and kidney damage. A reduction in the number of white blood cells has also been reported.
Tylenol (acetaminophen) side effects list for healthcare professionals
The following serious adverse reactions are discussed elsewhere in the labeling:
- Hepatic Injury
- Serious Skin Reactions
- Allergy and Hypersensitivity
Clinical Trial Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed cannot be directly compared to rates in other clinical trials and may not reflect the rates observed in practice.
A total of 1,020 adult patients have received acetaminophen in clinical trials, including 37.3% (n=380) who received 5 or more doses, and 17% (n=173) who received more than 10 doses. Most patients were treated with acetaminophen 1,000 mg every 6 hours. A total of 13.1% (n=134) received acetaminophen 650 mg every 4 hours.
All adverse reactions that occurred in adult patients treated with either acetaminophen or placebo in repeated dose, placebo-controlled clinical trials at an incidence = 3% and at a greater frequency than placebo are listed in Table 3. The most common adverse events in adult patients treated with acetaminophen (incidence = 5% and greater than placebo) were nausea, vomiting, headache, and insomnia.
|System Organ Class - Preferred Term||Acetaminophen|
|General Disorders and Administration Site Conditions Pyrexia*||22 (5)||52 (14)|
|Nervous System Disorders|
|39 (10)||33 (9)|
|30 (7)||21 (5)|
|* Pyrexia adverse reaction frequency data is included in order to alert healthcare practitioners that the antipyretic effects of acetaminophen may mask fever.|
Other Adverse Reactions Observed During Clinical Studies of Acetaminophen in Adults
The following additional treatment-emergent adverse reactions were reported by adult subjects treated with acetaminophen in all clinical trials (n=1,020) that occurred with an incidence of at least 1% and at a frequency greater than placebo (n=525).
Blood and lymphatic system disorders: anemia
Investigations: aspartate aminotransferase increased, breath sounds abnormal
Musculoskeletal and connective tissue disorders: muscle spasms, trismus
Psychiatric disorders: anxiety
Respiratory, thoracic and mediastinal disorders: dyspnea
A total of 355 pediatric patients (47 neonates, 64 infants, 171 children, and 73 adolescents) have received acetaminophen in active-controlled (n=250) and open-label clinical trials (n=225), including 59.7% (n=212) who received 5 or more doses and 43.1% (n=153) who received more than 10 doses. Pediatric patients received acetaminophen doses up to 15 mg/kg on an every 4 hours, every 6 hours, or every 8 hours schedule. The maximum exposure was 7.7, 6.4, 6.8, and 7.1 days in neonates, infants, children, and adolescents, respectively.
The most common adverse events (incidence = 5%) in pediatric patients treated with acetaminophen were nausea, vomiting, constipation, pruritus, agitation, and atelectasis.
Other Adverse Reactions Observed During Clinical Studies of Acetaminophen in Pediatrics
The following additional treatment-emergent adverse reactions were reported by pediatric subjects treated with acetaminophen (n=355) that occurred with an incidence of at least 1%.
Blood and lymphatic system disorders: anemia
Cardiac disorders: tachycardia
General disorders and administration site conditions: injection site pain, edema peripheral, pyrexia
Investigations: hepatic enzyme increase
Metabolism and nutrition disorders: hypoalbuminemia, hypokalemia, hypomagnesemia, hypophosphatemia, hypervolemia
Musculoskeletal and connective tissue disorders: muscle spasm, pain in extremity
Nervous system disorders: headache
Psychiatric disorders: insomnia
Renal and urinary disorders: oliguria
Skin and subcutaneous tissue disorders: periorbital edema, rash
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Effects of Other Substances on Acetaminophen
Substances that induce or regulate hepatic cytochrome enzyme CYP2E1 may alter the metabolism of acetaminophen and increase its hepatotoxic potential. The clinical consequences of these effects have not been established. Effects of ethanol are complex, because excessive alcohol usage can induce hepatic cytochromes, but ethanol also acts as a competitive inhibitor of the metabolism of acetaminophen.
Chronic oral acetaminophen use at a dose of 4,000 mg/day has been shown to cause an increase in international normalized ratio (INR) in some patients who have been stabilized on sodium warfarin as an anticoagulant. As no studies have been performed evaluating the short-term use of acetaminophen in patients on oral anticoagulants, more frequent assessment of INR may be appropriate in such circumstances.
Tylenol (acetaminophen) is an analgesic (pain reliever) and antipyretic (fever reducer) to relieve fever as well as aches and pains associated with many conditions. Tylenol relieves pain in mild arthritis but has no effect on the underlying inflammation, redness, and swelling of the joint. When used appropriately, side effects with Tylenol are not common.
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Related Disease Conditions
Fever in Adults and Children
Although a fever technically is any body temperature above the normal of 98.6 F (37 C), in practice, a person is usually not considered to have a significant fever until the temperature is above 100.4 F (38 C). Fever is part of the body's own disease-fighting arsenal; rising body temperatures apparently are capable of killing off many disease-producing organisms.
Lower Back Pain
There are many causes of back pain. Pain in the low back can relate to the bony lumbar spine, discs between the vertebrae, ligaments around the spine and discs, spinal cord and nerves, muscles of the low back, internal organs of the pelvis and abdomen, and the skin covering the lumbar area.
Foot pain may be caused by injuries (sprains, strains, bruises, and fractures), diseases (diabetes, Hansen disease, and gout), viruses, fungi, and bacteria (plantar warts and athlete's foot), or even ingrown toenails. Pain and tenderness may be accompanied by joint looseness, swelling, weakness, discoloration, and loss of function. Minor foot pain can usually be treated with rest, ice, compression, and elevation and OTC medications such as acetaminophen and ibuprofen. Severe pain should be treated by a medical professional.
Neck Pain (Cervical Pain)
Neck pain (cervical pain) may be caused by any number of disorders and diseases. Tenderness is another symptom of neck pain. Though treatment for neck pain really depends upon the cause, treatment typically may involve heat/ice application, traction, physical therapy, cortisone injection, topical anesthetic creams, and muscle relaxants.
Acute injuries, medical conditions, and chronic use conditions are causes of knee pain. Symptoms and signs that accompany knee pain include redness, swelling, difficulty walking, and locking of the knee. To diagnose knee pain, a physician will perform a physical exam and also may order X-rays, arthrocentesis, blood tests, or a CT scan or MRI. Treatment of knee pain depends upon the cause of the pain.
Arthritis, bursitis, IT band syndrome, fracture, and strain are just some of the causes of hip pain. Associated symptoms and signs include swelling, tenderness, difficulty sleeping on the hip, and loss of range of motion of the hip. Treatment depends upon the cause of the hip pain but may include anti-inflammatory medications and icing and resting the hip joint.
Ankle Pain (Tendinitis)
Ankle pain is commonly due to a sprain or tendinitis. The severity of ankle sprains ranges from mild (which can resolve within 24 hours) to severe (which can require surgical repair). Tendinitis of the ankle can be caused by trauma or inflammation.
Elbow pain is most often the result of tendinitis, which can affect the inner or outer elbow. Treatment includes ice, rest, and medication for inflammation. Inflammation, redness, warmth, swelling, tenderness, and decreased range of motion are other symptoms associated with elbow pain. Treatment for elbow pain depends upon the nature of the patient's underlying disease or condition.
Pain management and treatment can be simple or complex, according to its cause. There are two basic types of pain, nociceptive pain and neuropathic pain. Some causes of neuropathic pain include: complex regional pain syndrome, interstitial cystitis, and irritable bowel syndrome. There are a variety of methods to treat chronic pain, which are dependant on the type of pain experienced.
Chronic pain is pain (an unpleasant sense of discomfort) that persists or progresses over a long period of time. In contrast to acute pain that arises suddenly in response to a specific injury and is usually treatable, chronic pain persists over time and is often resistant to medical treatments.
Muscle Pain (Myofascial Pain Syndrome)
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