French to English Medical Medical (general) prescriptions post surgery

Context:
This is a list of prescribed drugs, starting with Paracetomol, then Ketoprofene LP, and then Pantoprozole, giving quantity and frequency for each, and then Nefopam Chlorhydrate.

The following is added after the prescription details for Pantoprozole:
'Si persistance des douleurs, associer aux prises précédentes et en alternance :'

and this is followed by the prescription details for Nefopram Chlorhydrate

Does this really mean 'combine with previous prescriptioinns'? (Even if it does, the meaning is a bit unclear, to me).