New laws are set to be introduced to make NHS patient health records available across all NHS trusts, GP surgeries and ambulance services in England.
The government estimates the move will save 140,000 hours of NHS staff's time every year, because staff will have quicker access to patient data.
However, campaign groups have warned that the move puts patients at risk of hacking and that the data might be sold.
Campaign group medConfidential raised concerns about confidentiality and data security, saying that patient records will be accessible by any of the NHS' 1.5 million staff, not just people with a legitimate interest in seeing it.