A new process is being brought in which will see both doctors and patients given a greater say in what drugs are approved for use on the NHS.
The Scottish Medicines Consortium (SMC) - the body which decides which treatments can be given to patients on the NHS - has announced changes to its systems, which are due to come into force from May this year.
It believes that in the first year as many as 1,500 people could get access to newly licensed medicines - at a potential cost of £70 million.
Health Secretary Alex Neil said he was "relaxed" about that as he hailed the changes to the SMC system.
"This is a major step that will revolutionise access to new medicines and make the system better for patients," he said.
"I believe it will lead to Scotland having a world-leading process."
The SMC has outlined how it will change its system for approving new drugs, by introducing Patient and Clinician Engagement (PACE) meetings to give patients' groups and doctors more say in decisions about treatment for those with life-limiting and rare conditions.
When considering if drugs aimed at helping those with very rare conditions - those affecting only about 100 people in Scotland - the SMC will also now consider more than just the direct health impact when making its decisions.
A new system to replace the Individual Patient Treatment Request (IPTR) system - used by patients to try to access drugs not yet approved by the SMC - will also be brought in from May, with the Peer Approved Clinical System (PACS) aiming to give clinicians more say in these decisions.
A review chaired by by Professor David Webb of Edinburgh University for the SMC said the changes would "deliver substantially improved access to medicines" for those with rare and end-of-life conditions.
The new system of PACE meetings would help provide "clarity on the clinicians' and patients' view on the need for the medicine" when decisions were being made, the review stated.
Mr Neil said he was "particularly pleased that SMC decisions will better reflect the views of patients and the doctors who treat them".
He added: "I firmly believe that such important decisions can only be made by those living with these conditions and our clinical experts".
The Health Secretary recalled: "Last year both the Scottish Parliament and Scottish Government made clear our wish to improve access to new medicines for patients at the end of life, or with rare conditions.
"I tasked the SMC with outlining how they could further enhance the new medicines approval process in Scotland to ensure that this improved access became a reality for patients.
"I know I'm not alone in welcoming their proposals, which are anticipated to help patients get new medicines quicker as they are more likely to be approved the first time they are submitted to the SMC, avoiding unnecessary time-consuming resubmissions."
While increased prescribing could cost as much as £70 million, Mr Neil said some of these costs would be met from the Rare Medicines Drugs Fund, which was set up last year to to help cover the cost of medicines for individual patients with rare conditions.
The Scottish Government is already committed to providing £20 million a year for this until 2016.
Mr Neil also said savings could come from a "massive extension" of the number of generic medicines that are available, and argued that prescribing new medicines to patients could result in them spending less time in hospital, thus saving cash for the NHS.
The changes are being made after the SMC was ordered to look at how it could increase flexibility when considering what drugs can be prescribed to people with rare conditions or terminal diseases.
SMC chair Professor Angela Timoney said: "These changes will mean that patients in need of end-of-life care or who have very rare conditions will be able to access more new medicines. We will actively engage with patient interest groups and clinicians to put these changes into practice and work with stakeholders to put resources in place to introduce these new changes as quickly as possible.
"These medicines have previously not been viewed as cost-effective by conventional measures and we have worked hard to find a way to enable access in Scotland. We look forward to putting our proposals in place."
James Jopling, the Scottish director for the health charity Breakthrough Breast Cancer, said the changes could result in more drugs being made available to patients "in their time of need".
He said: "Breakthrough Breast Cancer welcomes the enhanced role that patients and patients groups will now have in SMC decisions. By giving more weight to the value and benefit offered to patients by new medicines, we believe more drugs will be made available to those in their time of need.
"Last year, two very clinically effective medicines for secondary breast cancer were rejected for use on the grounds of cost, despite being highly valued by patients. These medicines would have given women precious additional quality time with their families and loved ones. We hope that the new system will allow drugs like these to be approved, giving hope to secondary breast cancer patients in Scotland."
Meanwhile Andrew Powrie-Smith, director of the Association of the British Pharmaceutical Industry in Scotland, said: "We welcome the Scottish Government's intent to ensure that patients in Scotland living with rare diseases or life-limiting illness get access to the new, innovative treatments they need.
"SMC has taken a collaborative approach to developing proposals and as an industry, we look forward to continuing to work with SMC, NHS Scotland and the Scottish Government to ensure patients see a real difference in the speed and availability of the treatments they need."
The changes to the SMC processes will be subject to a full review after a year.