UPDATE 1-Walgreens profit, sales beat estimates; boosts 2018 forecast

(Adds details on quarter, share price)

March 28 (Reuters) - Walgreens Boots Alliance Inc's quarterly profit and sales beat analysts' estimates on Wednesday, as the drugstore chain filled more prescriptions and kept costs down.

Shares of the Deerfield, Illinois-based company rose 4.8 percent to $69.11 in premarket trading.

The drug retailer also lifted its full-year adjusted earnings forecast to between $5.85 and $6.05 per share from $5.45 to $5.70 per share, reflecting benefits from changes to the U.S. tax code.

Walgreens expects more than $350 million in a cash tax benefit for fiscal year 2018, an increase of about $150 million from its previous estimate.

Same-store sales at Walgreens' U.S. pharmacies rose 5.1 percent in the quarter. The company filled 269.2 million prescriptions, up 9.1 percent from a year ago.

Excluding items, Walgreens earned $1.73 per share. Net sales rose 12 percent to $33.02 billion.

Analysts on average were expecting a profit of $1.55 per share on revenue of $32.19 billion, according to Thomson Reuters I/B/E/S.

Net income attributable to the company rose to $1.35 billion, or $1.36 per share, in the second quarter ended Feb. 28, from $1.06 billion, or 98 cents per share, a year earlier. (Reporting by Uday Sampath and Tamara Mathias in Bengaluru Editing by Saumyadeb Chakrabarty)