Try this (care of my Grandma)

1 cup activite
1 cup skim milk powder
1 litre milk

blend, and drink.

Day 1 drink whole litre over the course of the day.
Day 2 & 3 drink 1/2 litre per day
then 250ml a day as required.

I have about 1 250ml glass a week... more for the energy boost than anything else.