Tylenol 8 Hour Side Effects
Generic Name: acetaminophen
Medically reviewed by Drugs.com. Last updated on Nov 13, 2020.
Note: This document contains side effect information about acetaminophen. Some of the dosage forms listed on this page may not apply to the brand name Tylenol 8 Hour.
For the Consumer
Applies to acetaminophen: capsule, capsule liquid filled, elixir, liquid, powder, solution, suppository, suspension, syrup, tablet, tablet chewable, tablet disintegrating, tablet extended release
Other dosage forms:
Side effects requiring immediate medical attention
Along with its needed effects, acetaminophen (the active ingredient contained in Tylenol 8 Hour) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur while taking acetaminophen:
- 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
Get emergency help immediately if any of the following symptoms of overdose occur while taking acetaminophen:
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, 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 8 Hour) is well-tolerated when administered in therapeutic doses. The most commonly reported adverse reactions have included nausea, vomiting, constipation. Injection site pain and injection site reaction have been reported with the IV product.[Ref]
Common (1% to 10%): Increased aspartate aminotransferase
Rare (less than 0.1%): Increased hepatic transaminases
Frequency not reported: Liver failure[Ref]
Very common (10% or more): Nausea (up to 34%), Vomiting (up to 15%)
Frequency not reported: Dry mouth[Ref]
Common (1% to 10%): Anemia, postoperative hemorrhage
Common (1% to 10%): Rash, pruritus
Common (1% to 10%): Headache, dizziness
Frequency not reported: Dystonia
Common (1% to 10%): Muscle spasms, trismus
Common (1% to 10%): Oliguria
Common (1% to 10%): Infusion site pain, injection site reactions
Common (1% to 10%): Periorbital edema
Common (1% to 10%): Pyrexia, fatigue
Rare (0.01% to 0.1%): Malaise
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More about Tylenol 8 Hour (acetaminophen)
- During Pregnancy or Breastfeeding
- Dosage Information
- Drug Images
- Drug Interactions
- 6 Reviews
- Drug class: miscellaneous analgesics
- FDA Alerts (15)
Related treatment guides
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Some side effects may not be reported. You may report them to the FDA.