The National Institute for Health and Clinical Excellence (Nice) has taken responsibility for helping the NHS to optimise its use of medicines with its absorption of the National Prescribing Centre (NPC).
NPC's activities have been retained and became part of a new work programme within the Evidence and Practice Directorate.
Nice's additional functions could potentially create a conflict of interest within the organisation as the NPC provided information for health professionals to support the managed introduction of newly licensed or marketed medicines (such as where there is not yet NICE guidance).
It is now in charge of deciding which treatments and practices the NHS should adopt and how it should do them most cost effectively and efficiently.
The merger was approved by the Department of Health in October as part of its plans to restructure the NHS.
Other NPC duties included: Offering advice and support to non-medical prescribers (such as pharmacists, nurses and optometrists) about medicines in line with the NHS Constitution (e.g. individual funding requests); MeReC bulletins, which provide concise, evidence-based information about a variety of medicines and prescribing.
Dr Gillian Leng, deputy chief executive of Nice, said: "The NPC and Nice already share a history of working closely together in helping ensure medicine usage across the NHS is high quality, safe and good value for money.
"This integration is an exciting opportunity for us to build on the important work that we both do in all aspects of medicines management and will further strengthen access to medicines information through NHS Evidence."