Patients will be able to examine data on the safety of different medicines, the government has announced.
Drug data will be published on the web
Anonymised data on suspected adverse drug reactions will be published on the Medicines and Healthcare products Regulatory Agency website.
Researchers will be able to access more detailed information.
The move is part of a series of measures to improve the system for reporting and monitoring side effects - known as the Yellow Card Scheme.
There have been concerns that not all side effects are reported under the scheme, and that information generated by the system has not been properly analysed.
Measures will be put in place to prevent potential abuse of the information.
Every request from a researchers will be reviewed by an independent committee to make sure it is ethically and scientifically sound and protects patient confidentiality.
In addition, the Department of Health has launched pilot schemes which will allow patients to report adverse drug reactions directly to the regulator.
Forms to report unexpected drug reactions will be available in 4,000 GP surgeries across the UK and patients will also be able to make reports online.
Health Minister Lord Warner said the Yellow Card Scheme was already effective, but the reforms would improve it still further.
"The data generated through the scheme can be used to further research and improve drug safety in the UK - patients can see the information used to make decisions about medicines safety and researchers can use this important resource to aid research.
"Enabling patients to directly report unexpected drug reactions allows them to play their part in making medicines safer and help the experts better monitor drug safety and protect public health".
The new measures were recommended made by experts who reviewed the yellow card scheme last year and a public consultation.
Sir Alasdair Breckenridge, MHRA chairman, said: "The Yellow Card Scheme is an important way that the MHRA monitors drug safety.
"It is only right that others can also benefit from the data.
"Research based on Yellow Card data could have enormous public health benefits and by enabling researchers to access the data we will be playing our part in promoting this important research."
The Yellow Card Scheme was set up in 1964 following the Thalidomide tragedy to provide a system for early detection of emerging drug safety hazards and the routine monitoring for all medicines in clinical use.
Suspected adverse reactions are reported to the Committee on Safety of Medicines (CSM) and MHRA, which are jointly responsible for running the scheme.
Until now, reports have been primarily submitted voluntarily by GPs, hospital doctors, dentists, coroners, pharmacists and nurses.
Shadow Health Minister Tim Loughton said: "Given recent concerns over prescribing policy of anti-depressants it is vital that the public have confidence in the drugs they are taking.
"That is why we have long called for all the data from clinical trials to be published by the MHRA in as accessible a way as possible, and we welcome the news that drugs companies themselves are also increasingly volunteering this information."
Mr Loughton said the Yellow Card scheme was good in principle - but there was strong evidence to suggest that there was massive under-reporting of patient concerns through GPs.
"It is essential that all patients are able to report their concerns about the side-effects of some drugs and dosages, not just a small minority as the government still appears to be catering for."