Nested IF functions

Originally Posted by NBVC

And are there still going to be inputs in columns C and D?

I've coloured the column in yellow which the expected values are. Above the yellow the if formula is calculating the values correctly, but after the yellow starts I need a formula that will reduce the value by 12.5 every second day (to correspond with the end of the life of that dose in the blood).

After day 32 there will be no more values in column c and d as there will be no more dosing with the drug. The drug will then exit the blood stream based on the life, 32 days, so each initial dose will no longer release 12.5 into the blood stream after 32 days from that dose.