Ibuprofen generally starts working within 20 to 30 minutes after taking it orally. The maximum pain relief is typically experienced within 1 to 2 hours. The duration of effective pain relief from a single dose usually lasts about 4 to 6 hours. Taking ibuprofen on an empty stomach can make it work faster, though it may increase the risk of stomach upset. Food slows the absorption but doesn't reduce the amount absorbed overall. For chronic conditions, it may take several days of regular dosing to notice significant pain relief from inflammation reduction.
