(in)compatibility of 2 raw materials

Dear Professor,

A GP wrote the following preparation against 'bone pains':

R/ calcium carbonate 200mg
disodium phosphate 500mg p.g.u.
DT 60 caps
S/ 1/day 6 days out of 7 and on day 7 intake of risedronate

Are these 2 raw materials not taken separately, since the incompatibility of phosphates with calcium salts?

Thanks in advance.

Mvg,
Adebayo Dare