Tylenol Side Effects
Generic Name: acetaminophen
Note: This page contains side effects data for the generic drug acetaminophen. It is possible that some of the dosage forms included below may not apply to the brand name Tylenol.
It is possible that some side effects of Tylenol may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.
For the Consumer
Applies to acetaminophen: capsule, capsule liquid filled, elixir, liquid, powder, powder for solution, solution, suppository, suspension, syrup, tablet, tablet chewable, tablet disintegrating, tablet effervescent, tablet extended release
As well as its needed effects, acetaminophen (the active ingredient contained in Tylenol) may cause unwanted side effects that require medical attention.
If any of the following side effects occur while taking acetaminophen, check with your doctor immediately:Rare
- Bloody or black, tarry stools
- bloody or cloudy urine
- fever with or without chills (not present before treatment and not caused by the condition being treated)
- pain in the lower back and/or side (severe and/or sharp)
- pinpoint red spots on the skin
- skin rash, hives, or itching
- sore throat (not present before treatment and not caused by the condition being treated)
- sores, ulcers, or white spots on the lips or in the mouth
- sudden decrease in the amount of urine
- unusual bleeding or bruising
- unusual tiredness or weakness
- yellow eyes or skin
If any of the following symptoms of overdose occur while taking acetaminophen, get emergency help immediately:Symptoms of overdose
- increased sweating
- loss of appetite
- nausea or vomiting
- stomach cramps or pain
- swelling, pain, or tenderness in the upper abdomen or stomach area
For Healthcare Professionals
Applies to acetaminophen: compounding powder, intravenous solution, oral capsule, oral granule effervescent, oral liquid, oral powder for reconstitution, oral suspension, oral tablet, oral tablet chewable, oral tablet disintegrating, oral tablet extended release, rectal suppository
In general, acetaminophen (the active ingredient contained in Tylenol) is well-tolerated when administered in therapeutic doses.
Alcoholic patients may develop hepatotoxicity after even modest doses of acetaminophen (the active ingredient contained in Tylenol) In healthy patients, approximately 15 grams of acetaminophen is necessary to deplete liver glutathione stores by 70% in a 70 kg person. However, hepatotoxicity has been reported following smaller doses. Glutathione concentrations may be repleted by the antidote N-acetylcysteine. One case report has suggested that hypothermia may also be beneficial in decreasing liver damage during overdose.
In a recent retrospective study of 306 patients admitted for acetaminophen overdose, 6.9% had severe liver injury but all recovered. None of the 306 patients died.
A 19-year-old female developed hepatotoxicity, reactive plasmacytosis and agranulocytosis followed by a leukemoid reaction after acute acetaminophen toxicity.
Hepatic side effects including severe and sometimes fatal dose dependent hepatitis have been reported in alcoholic patients. Hepatotoxicity has been increased during fasting. Several cases of hepatotoxicity from chronic acetaminophen therapy at therapeutic doses have also been reported despite a lack of risk factors for toxicity.
One study has suggested that acetaminophen (the active ingredient contained in Tylenol) may precipitate acute biliary pain and cholestasis. The mechanism of this effect may be related to inhibition of prostaglandin and alterations in the regulation of the sphincter of Oddi.
Gastrointestinal side effects have included nausea (34%) and vomiting (15%). Cases of acute pancreatitis have been reported rarely.
Renal side effects are rare and have included acute renal failure, acute tubular necrosis, and interstitial nephritis. Adverse renal effects are most often observed after overdose, after chronic abuse (often with multiple analgesics), or in association with acetaminophen-related hepatotoxicity.
Acute tubular necrosis usually occurs in conjunction with liver failure, but has been observed as an isolated finding in rare cases. A possible increase in the risk of renal cell carcinoma has been associated with chronic acetaminophen use as well.
One case-control study of patients with end-stage renal disease suggested that long term consumption of acetaminophen may significantly increase the risk of end-stage renal disease particularly in patients taking more than two pills per day.
However, a recent cohort study of analgesia use of initially healthy men concluded that moderate use of analgesics including acetaminophen was not associated with increased risk of renal disease.
Hypersensitivity side effects including anaphylaxis and fixed drug eruptions have been reported rarely in association with acetaminophen (the active ingredient contained in Tylenol) use.
Hematologic side effects including rare cases of thrombocytopenia associated with acetaminophen (the active ingredient contained in Tylenol) have been reported. Acute thrombocytopenia has also been reported as having been caused by sensitivity to acetaminophen glucuronide, the major metabolite of acetaminophen. Methemoglobinemia with resulting cyanosis has been observed in the setting of acute overdose.
Dermatologic side effects including erythematous skin rashes associated with acetaminophen (the active ingredient contained in Tylenol) have been reported, but are rare. Acetaminophen associated bullous erythema and purpura fulminans have been reported. One case of toxic epidermal necrolysis associated with acetaminophen administered to a pediatric patient has been reported. Dermatologic side effects associated with IV acetaminophen have included infusion site pain and peripheral edema.
Very rare potentially fatal skin reactions: Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP).
Respiratory side effects have included dyspnea and a case of acetaminophen-induced eosinophilic pneumonia.
Two cases hypotension have been reported following the administration of acetaminophen (the active ingredient contained in Tylenol) Both patients experienced significant decreases in blood pressure. One of the two patients required pressor agents to maintain adequate mean arterial pressures. Neither episode was associated with symptoms of anaphylaxis. Neither patient was rechallenged after resolution of the initial episode.
Cardiovascular side effects including hypertension and hypotension have been reported following the administration of acetaminophen.
Metabolic side effects have included hypokalemia. Metabolic side effects including metabolic acidosis have been reported following a massive overdose of acetaminophen (the active ingredient contained in Tylenol)
In the case of metabolic acidosis, causality is uncertain as more than one drug was ingested. The case of metabolic acidosis followed the ingestion of 75 grams of acetaminophen, 1.95 grams of aspirin, and a small amount of a liquid household cleaner. The patient also had a history of seizures which the authors reported may have contributed to an increased lactate level indicative of metabolic acidosis.
Nervous system side effects associated with IV acetaminophen (the active ingredient contained in Tylenol) have included headache (10%), insomnia (7%), and fatigue.
Musculoskeletal side effects associated with acetaminophen (the active ingredient contained in Tylenol) IV have included muscle spasms and trismus.
Psychiatric side effects associated with acetaminophen (the active ingredient contained in Tylenol) IV have included anxiety.
More about Tylenol (acetaminophen)
- Tylenol suppositories
- Tylenol Caplet
- Tylenol Rapid Release Gelcap
- Tylenol Suspension oral/rectal
- Tylenol (Advanced Reading)
Related treatment guides
Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.