The cost and number of items prescribed in Scotland is rising, prompting fears that health boards will struggle to balance their books.
New figures from the NHS Information Services Division (ISD) show that the total cost of prescribing in Scotland increased by 3.2% to £1.18 billion in 2011-12 compared with the previous year.
In addition, the number of prescription items increased by 3.8% to 94.6 million in the same year.
The amount of prescribing has risen steadily over the past 10 years and the ISD statistics show that prescribing volumes increased from 69.5 million in 2002-03 to 94.6 million items in 2011-12.
The ISD said this growth reflected the availability of new or more effective medicines, increasing patient expectation, demographic changes, and the implementation of clinical guidelines and recommendations.
The resulting net cost has also risen and in the past 10 years from 2002-03 to 2011-12 this cost has increased from £840.6 million to £1.18 billion.
GPs write the vast majority of prescriptions, with the remainder written by authorised prescribers such as nurses and dentists.
The most commonly prescribed drug in 2011-12 by volume was simvastatin (used for controlling cholesterol), replacing aspirin for the first time.
Salmeterol with fluticasone proprionate (used for respiratory conditions) was the most expensive by gross ingredient cost in 2011-12, replacing atorvastatin for the first time.
Geographically, NHS Lothian had the lowest items (13.1) and net cost (£179.69) per person on a GP list size, while NHS Western Isles had the highest in terms of items (23.7) and NHS Ayrshire and Arran in terms of net cost (£231.75) in 2011-12.
The Royal College of Nursing said the figures were a cause for concern.
Its Scotland director Theresa Fyffe: “Our own analysis found that nine of the fourteen territorial health boards [in Scotland] overspent on GP prescribing to the tune of £18 million last financial year.
“This latest increase in prescribing costs, on top of years of growing spend on prescribing, comes at a time when the overall health budget is virtually at a standstill.
“The pressure is mounting on health boards to make increasingly difficult decisions to balance their books while still maintaining quality services that meet growing patient demand.
“That is why we have consistently called for health boards to be more open and honest about what they currently spend their money on and what their plans for the future consist of.”
The Scottish Government abolished prescription charges in Scotland last April.
A BMA Scotland spokesperson said: “Patients with chronic and life threatening illnesses who need regular medication are now able to get their medicines without having to worry about the cost.
“Doctors saw first hand how patients had to contend with the inequalities of the previous charging system. They are now able to write prescriptions in the knowledge that cost won’t be a factor in preventing patients from taking their medicines. However, the wider impact of this policy must be kept under review.”