Vicodin es opposed to Norco

My doctor prescribed hydrococodone 10/325 for me due to RA. The pharmacist gave me Norco10/325, but it makes me VERY tired, I cannot function on these pills...What is the difference between the hydrcodone & the Norco? The vicodin does NOT make me drowsy.. I need to see my doctor this week & tell him that i need a new prescription, instead of the norco. I need to know what the difference is please. Thank You in Advance, Lois R.