The number of prescriptions for Viagra and other erectile dysfunction drugs has gone up by more than a quarter in a year, official figures show.

Statistics released by the Health and Social Care Information Centre (HSCIC) show that last year there were 1.7 million prescriptions for sildenafil - commonly sold as Viagra but also available under other trade names - compared with 1.4 million in 2013 and a million in 2004.

Antidepressants, which include drugs for depressive illness, generalised anxiety disorder (GAD), obsessive-compulsive disorder, and panic attacks, also saw a large increase with 57.1 million dispensed last year, up 7.2% from 53.3 million in 2013.

Since 2004 the number has nearly doubled by 97.1% from 29 million.

HSCIC said more than 1.06 billion items were prescribed in England last year, an increase of 3.3% on 2013 and a rise of 55.2% on 2004.

The overall net ingredient cost (NIC) of prescriptions last year stood at £8.85 billion, up 2.6% on 2013 and 9.6% over the last decade.

While the number of prescriptions for erectile dysfunction drugs has gone up, the cost of sildenafil fell by 85.9% as generic alternatives became available in 2013, HSCIC said.

The most money was spent on drugs for diabetes for the eighth year in succession, rising by £55.3 million (7%) in a year to £849.1 million last year.

Atorvastatin, which helps to reduce the likelihood of heart attacks and strokes, had the greatest increase in the number of items dispensed with 4 million more since 2013.

The report shows the average NIC per prescription item dispensed in the community had decreased by 29.4% since 2004.

Of all prescription items dispensed the vast majority - 89.9% (957.1 million) - were free of charge.

Three in five were for patients aged 60 and over, accounting for 51.2% (£4.53 billion) of the total NIC for all prescriptions.

One in 20 was for patients aged under 16 or 16-18 and in full-time education.

The report looks at prescriptions dispensed by community pharmacists, dispensing doctors and in GP practices.