Consumption and sales data of UK prescription medicines for 2018 is now available on Pharma14.
This includes pharmacy and hospital channels for England, Scotland, Wales and N. Ireland.
In overall numbers, the cost of prescriptions dispensed in 2018 was USD 13.54 billion . A small but significant decrease of 3.7% from USD 14.07 billion in 2017
In 2018 as well as in 2017 roughly 1.3 billion medicines were prescribed in the UK with a slight increase of 0.3% from 2017 to 2018. 

Sample data: Enoxaparin 100 mg and 150 mg injection consumption and sales.
2017 vs. 2018 data including consumption and sales movement.
Note: Generic Arovi came onto the market in 2018. (Line 8).