Prescriptions are now costing the NHS in Scotland £1.07bn a year, latest figures show.

The cost - which was £598m 10 years ago - stands at £196.20 for every person registered with a doctor.

Higher production costs and an increased volume of prescriptions being issued were given as causes for the rise.

The Scottish government is currently phasing out prescription charges, with a view to abolishing them completely by 2011. An individual prescription item cost £6.85 in December 2007 when phasing out started. It will be cut to £3 per item next year before becoming free in 2011.

In England, prescription charges are £7.10 per item, but people aged over 60 or under 16, pregnant women and new mothers are exempt.

The data, published by NHS statistical service ISD Scotland, showed that aspirin was the most prescribed drug. The most expensive was Atorvastatin, which is used to control cholesterol.

In the first quarter of 2009-10, about 1.3 million prescriptions were dispensed to patients holding a valid pre-payment certificate, an 18 per cent increase on the same quarter last year.