Prednisone usually starts working very quickly, often within a few hours to a couple of days after taking the first dose. The exact timing depends on the condition being treated and the formulation of prednisone. Immediate-release forms absorb into the bloodstream within about 2 hours, while delayed-release tablets take about 6 hours to start working. Some people may notice effects within hours, but generally, the medication's anti-inflammatory effects are observed within 1 to 4 days if the dose is effective.