January 1, 2017, marked the implementation date of a change to the marketing status of water soluble antimicrobials for use in food animals.  13 established drugs will switch from over-the-counter (OTC) to Rx status at the beginning of 2017.  This change has been in the pipeline since December of 2013, when drug companies were asked by the Food and Drug Administration (FDA) to voluntarily change product labels to remove claims of growth promotion.  Between December 2013 and December 2016 drug sponsors have been preparing for the switch, in concert with FDA timeline guidelines.  These changes are being instituted to stop the use of medically-important antibiotics for non-therapeutic uses in the mass medication of food animals. 

Water soluble antimicrobials used to make “medicated water” may only be dispensed by or on the prescription order of a licensed veterinarian that has a valid Veterinarian –Client- Patient Relationship (VCPR).  In the past, businesses such as feed mills and farm supply stores have stocked and sold these antimicrobials for the over-the-counter use.  This practice will not be lawful as of January 1, 2017.  End-users of the antimicrobials will need to obtain the prescription drugs from a pharmacy licensed by the Iowa Board of Pharmacy or directly from the prescribing veterinarian. 

The following water soluble drugs will move from OTC to Rx status:

  • Chlortetracycline
  • Erythromycin
  • Gentamicin
  • Lincomycin
  • Lincomycin/Spectinomycin
  • Neomycin
  • Oxytetracycline
  • Penicillin
  • Spectinomycin
  • Sulfadimethoxine
  • Sulfaquinoxaline
  • Tetracycline

A list of these drugs along with common trade or propriety names for each can be found on the FDA's website through the following link:


Businesses must be properly licensed with the Board of pharmacy to obtain, distribute or dispense prescription drugs in or into the state of Iowa.  Please contact Jennifer Tiffany with the Iowa Board of Pharmacy at 515-242-5139 with questions or concerns.