DEERFIELD, Ill. — Walgreen Co. has lost two executives to retirement who collectively had spent more than a half-century with the retailer.

Both John Spina and Don ­Huon­ker retired on October 31, the company says.

Spina, corporate vice president of expense optimization, had the longer tenure of the two. He joined Walgreens in 1979 as a store clerk in Daly City, Calif. He moved into store management and in 1996 became a district manager in Knoxville, Tenn.

Spina was promoted to director of drug store administration in 2003 and two years later was promoted again to the role of vice president of store operations. He became vice president of retail integration and new format development in 2009. He played key roles in the acquisition and integration of the Duane Reade drug store chain in greater New York and development of the Well Experience store format.

Huonker joined Walgreens in 1995 as a pharmacist and management trainee in St. Louis. He moved to the corporate office in 2001. He oversaw Walgreens’ health information technology development. Since April, he had been the company’s chief operational risk officer.