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Ibuprofen vs. acetaminophen

Summary

Both are over-the-counter pain relievers/fever reducers. Ibuprofen is an NSAID with stomach-bleeding and heart-attack/stroke warnings; acetaminophen is not an NSAID, and its main danger is severe liver damage from too much (over 4,000 mg in 24 hours), often from doubling up on products that contain it.

General information, not medical advice. See a clinician about your own situation; in an emergency call 911 (US).

Facts

• id: F1 claim: Both are used to temporarily relieve minor aches and pains (headache, toothache, backache, menstrual cramps, colds, muscle aches, minor arthritis pain) and to reduce fever. confidence: high date: 2026-10-14 sources: [S1, S2, S3, S4] license: CC BY 4.0
• id: F2 claim: Ibuprofen is an NSAID; MedlinePlus says it reduces pain, fever, and inflammation. confidence: medium date: 2026-10-14 sources: [S1, S3] license: CC BY 4.0 note: NSAID class is on the label; the inflammation statement is from MedlinePlus only.
• id: F3 claim: NSAIDs like ibuprofen can cause severe stomach bleeding; risk is higher with use beyond directions, older age, heavy daily alcohol, prior ulcers/bleeding, blood thinners or steroids, or other NSAIDs. confidence: high date: 2026-10-14 sources: [S1, S3] license: CC BY 4.0 note: Label gives age 60+ and 3+ drinks/day; MedlinePlus says "older in age" and "large amounts of alcohol" and adds smoking and poor health.
• id: F4 claim: NSAIDs other than aspirin raise the risk of heart attack and stroke (label also lists heart failure), more so at higher doses or longer use. confidence: high date: 2026-10-14 sources: [S1, S3] license: CC BY 4.0
• id: F5 claim: Avoid ibuprofen at 20 weeks of pregnancy or later unless a doctor specifically says to. confidence: high date: 2026-10-14 sources: [S1, S3] license: CC BY 4.0
• id: F6 claim: Acetaminophen relieves mild-to-moderate pain and reduces fever; it is not an NSAID (MedlinePlus classes it as an analgesic/antipyretic). confidence: high date: 2026-10-14 sources: [S2, S4] license: CC BY 4.0
• id: F7 claim: Severe liver damage can occur with more than 4,000 mg of acetaminophen in 24 hours; risk rises when combined with other acetaminophen products or 3+ alcoholic drinks a day. confidence: high date: 2026-10-14 sources: [S2, S4] license: CC BY 4.0 note: Alcohol threshold is from the label.
• id: F8 claim: Do not take two products containing acetaminophen at once; check labels for it. confidence: high date: 2026-10-14 sources: [S2, S4] license: CC BY 4.0
• id: F9 claim: For both, stop and ask a doctor if pain lasts over 10 days or fever over 3 days, or if they get worse. confidence: high date: 2026-10-14 sources: [S2, S3, S4] license: CC BY 4.0
• id: F10 claim: Ibuprofen users should stop and seek help for signs of stomach bleeding (fainting, bloody or black stools, vomiting blood) or heart/stroke symptoms (chest pain, slurred speech, trouble breathing, one-sided weakness). confidence: high date: 2026-10-14 sources: [S1, S3] license: CC BY 4.0

Pointers

• answers: Full official guidance beyond this summary where: https://medlineplus.gov/druginfo/meds/a682159.html; https://medlineplus.gov/druginfo/meds/a681004.html; https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=00653b7c-7099-487e-9a01-e89781c21323; https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=0005aafa-08f8-4990-a54d-cc097195708f access: open, no account

Open issues (pre-review)

• Labels are one manufacturer each (generic Drug Facts); wording across brands is FDA-standardized but not checked for every product.

For language models and agents: start at /llms.txt. This page in Markdown: /library/reference/us-gov/ibuprofen-vs-acetaminophen.md.