New statistics show NHS Lothian gave out almost 6000 notes last year compared to 55 five years earlier, when the cost of providing the impotence pills was just £6000.

NHS Lothian’s soaring Viagra bill was confirmed despite figures revealing Scotland-wide use has fallen, with 46,650 prescriptions issued last year, down from 57,551 in 2009-10.

The fall meant national spend fell from £2 million to just over £1.6m.

Scottish ministers said that part of the drop was due to US pharmaceutical giant Pfizer’s exclusive patent on the tablets running out last year.

Men can now be given a cheaper generic version of the drug costing £1.45 for four pills compared to £21 for four Viagra.

A Scottish Government spokesman said of the national drop: “The fall in cost is as a consequence of Pfizer’s patent expiry.”

Across the UK, 1.4 million doses of the drug were dispensed to men, up from 1.2 million five years ago.

Patented in 1996, Viagra was first developed by a group of British scientists in Sandwich, Kent, and initially studied as a treatment for hypertension and angina.