Walgreens, one of the largest US pharmacy and drug store chains, is to start operating workplace health clinics for companies such as Continental Airlines, BMW and Toyota, in a strategic expansion into health and wellbeing services.

The company, which operates more than 6,000 retail pharmacies, said it has agreed a $278m deal to acquire I-trax, which operates workplace clinics, wellness centres and pharmacies for more than 160 companies. It is also paying an undisclosed sum for Whole Health Management, which provides on-site health services for 27 companies.