Our History

Diamond is the nation’s largest correctional pharmacy provider and Pennsylvania’s largest independently owned long term care pharmacy.

In 1970, Gilbert and Joan Zilner, both pharmacists, purchased a retail pharmacy located in downtown Indiana, Pennsylvania.  Diamond Pharmacy’s success began here and continued when their son, Mark Zilner, joined the business in 1991.  Mark provided new perspective and energy, helping to improve, enhance, and add features that have led to an expansion of Diamond’s services.

Due to the personalized service and cost effective pricing, Diamond has experienced tremendous growth in recent years.  In addition to our 135,000 square foot state-of-the-art institutional pharmacy, we operate an IV infusion facility, two retail pharmacies, and a medical supply division.  Diamond recently opened a satellite pharmacy in Reading Pennsylvania in order to better service the eastern side of the state.  Combining the values of a family owned business with cutting edge technology, Diamond has become a company which combines the latest in industry technology and leading experience with old-fashioned hard work.  We offer our customers the advantages of a large company with the service and approach of a family owned, home-town pharmacy.

In 2001, Diamond surpassed all competition to become the Nation’s largest correctional pharmacy services provider.  Continuing to lead the way, Diamond understands the responsibilities associated with satisfying the needs and exceeding the expectations of all our customers and facilities.

Diamond is accredited by The Joint Commission, whose criteria set the standards on quality patient care. Diamond’s Medical Supply and Infusion Division are also accredited by The Joint Commission.