Hi debby, welcome!  Are you referring to the osteoporosis drugs?  If so, you need to have enough calcium in your diet for these medications to work.  If you look at any of the osteoporosis drugs patient inserts, they all say that you need to correct calcium and vitamin D deficiency for these drugs to work.

Here's one for Reclast.  You can look at any of them (Actonel, Boniva, Forteo, Prolia etc.) and see that it says the same thing for each.  Mineral metabolism problems can cause bone loss, so you need to take adequate D and calcium so you'll metabolize the medication properly.

To check for vitamin D levels, your doctor can order a 25 (OH) D test and for calcium you would want to have a total calcium blood test and possibly a 24 hour urine test to see if you are excreting the calcium too fast and not utilizing it first.

Most of these meds can cause a lowering of your calcium level (hypocalcemia) so be sure to get adequate calcium from you diet and supplement if the amount you eat is too low.  Most recommendations are around 1,200 mgs a day for Ca and you'll need to test your D level and have your doctor tell you how much of this you will need.

Good Luck!