The Slough-based group, which owns brands including Harpic, Dettol and Durex, also made big strides in its rapidly-expanding markets of India, Brazil and China, driving 6% underlying revenues growth during the first three months of the year.
Total revenues improved 7% to £2.5 billion and Reckitt said it is confident of achieving 5-6% growth for the year despite "continued challenging market conditions".
Reckitt benefited from a spate of flu and colds in the United States, with successful launches of new products such as Strepsils lozenges for children and Nurofen heat patches.
Other innovations such as Mucinex Fast Max and Sinus Max decongestants drove growth in the US, helping its European and North American division increase underlying sales 3% amid sluggish consumer spending.
Its Latin America and Asia Pacific region was the star performer once again, with growth of 11% driven by strong sales of Durex in China, plus good performance from Gaviscon heartburn treatment, Vanish stain remover and Air Wick air freshener.
Reckitt is battling newly-introduced generic competition in its highly profitable pharmaceuticals business. Rivals' generic tablets have so far taken 10% market share since their recent launch.
But Keith Bowman, an equity analyst at Hargreaves Lansdown stockbrokers, said the update reassured investors.
He added: "Competitors are also targeting emerging market growth, whilst a near 30% gain in the share price over the last year alone does raise some valuation question marks."