Ibuprofen typically stays in your system for about 10 hours after a standard dose, such as 400 mg. This is based on its half-life of approximately 1.8 to 2.2 hours, meaning it takes about 4 to 5 half-lives (roughly 10 hours) for the drug to be mostly eliminated from the body

. The drug is rapidly absorbed, reaching peak blood levels within 1 to 2 hours, and its pain-relieving effects last about 4 to 6 hours

. Ibuprofen is metabolized primarily by the liver into inactive compounds, which are then excreted mainly through the urine

. Complete elimination can take up to 24 hours, but for practical purposes, the drug is considered cleared after about 10 hours in healthy individuals

. Factors that can prolong ibuprofen’s presence in the body include higher doses, frequent use, slower metabolism due to age, liver or kidney impairment, and interactions with other medications

. In such cases, ibuprofen or its metabolites may linger longer than the typical 10-hour window. In summary:

• Half-life: ~1.8 to 2.2 hours
• Time to mostly clear: ~10 hours (4-5 half-lives)
• Complete elimination: up to 24 hours
• Metabolized by liver, excreted in urine
• Duration of pain relief: 4-6 hours
• Clearance affected by dose, metabolism, liver/kidney function, and drug interactions