The?Dow Jones?was up 106.61 points, or 0.7%, at 16,383.30 about an hour after trading began.
The tech-heavy?Nasdaq?index rose 31.64 points to 4,258.02, while the broader?S&P 500?index was 10 points higher at 1,867.44.
Health care, energy and technology stocks were among the biggest risers, reversing losses seen on Monday.
Shares in drugstore chain?Walgreen?rose 4.25% despite the company reporting a lower-than-expected quarterly profit.
Net income dipped to $754m from $756m a year earlier, although sales rose 5.1% to $19.61bn.
Cruise operator?Carnival?fell 3.4% after it predicted full-year adjusted profit of $1.50-$1.70 a share, which was below analysts’ expectations.
The company has been cutting prices to boost demand for its cruises.