When the market price of a generic product declines to a point where manufacturers can no longer make a profit, they may decide to cancel or not commission the next batch of stock. Consequently, the price goes up as the available stock in the market declines.
The low price that triggers the spike in value does seem to be reasonably consistent, although some variability exists. For example, in the case of ‘Pramipexole Tabs 350mcg 100’, the first spike was triggered by a low price of £14.66, the second by £ 13.88 & the third by £14.48. This gives a picture of some consistency in that prices below £15 may cause a reduction in available stock, a shortage and a price spike.
Risedronate Sodium Tabs 30mg 28 on the other hand, has a series of highly variable low trigger points (£47.02, £39.82, £77.06, £49.06, £26.51). This suggests that something else is controlling the point at which manufacturers cancel stock orders.
The graph below shows that products with tall bars, have more variable trigger prices, such as ‘Risedronate Sodium Tabs 30mg 28’. Whereas those with smaller bars, such as ‘Pramipexole Tabs 350mcg 100’, display the trigger prices are more consistent.