A majority stake in the Sam McCauley Chemists chain has been sold to private equity fund Carlyle Cardinal Ireland (CCI).
The investment is expected to close before the end of the summer and is understood to be worth €50m.
Tony McEntee, a former CEO of Allcare Pharmacy Group and previously finance director of Lifestyle Sports, will join the company as CEO following the completion of the investment.
The current managing director of the Sam McCauley chain, Patrick McCormack, will step down.
Sam McCauley himself will remain with the business and retain a minority stake after the sale.
Backing from CCI sets the business up as a consolidator in what remains a highly fragmented market. No single pharmacy chain has more than a 5pc share of the Irish market.
Starting with a single shop in Enniscorthy, Co Wexford, in 1978, the Sam McCauley chain is the third-largest retail pharmacy group in Ireland. It has 30 stores and almost 600 employees and had turnover of €75m in 2015.
"The health and well-being of our customers is at the heart of everything we do at Sam McCauley's. We have maintained that customer focus and high degree of service as the business expanded in size over the years through a continuous focus on introducing new products and services," Sam McAuley said.
"The investment from CCI allows us to continue this growth as an Irish-owned business and will accelerate future innovations for the benefit of our customers and for the development of our loyal employees," he added.
Mr McCauley will continue as a significant shareholder of the company and remain on the board of directors alongside CCI's Ian Daly and Jonathan Cosgrave.
Mr McCauley thanked Patrick McCormack for his services and said that he looked forward to working with Mr McEntee, during what he said was an "exciting next stage in the company's evolution".
CCI has been an active growth investor in the Irish market over the last three years.
Sam McCauley Chemists Limited is the fund's eighth investment and the fund continues to explore other investment opportunities.
Current fund investments include The AA Ireland, Payzone, Carroll Cuisine, Lily O'Brien's, General Secure Logistics Services (GSLS), Learning Pool and Abtran.
Upon completion of the Sam McCauley investment, the CCI portfolio companies will employ more than 4,000 people across Ireland.