Thyroid Preparations/Ciprofloxacin Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Taking thyroid medicines and ciprofloxacin at the same time may decrease the amount of thyroid hormone in your body.

What might happen:

Your thyroid medicine may not work as well. Signs and symptoms to look for include: feeling tired, dry skin and brittle nails,and not being able to stand the cold, constipation, depression.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. You may need to separate the times you take your thyroid medicine and ciprofloxacin.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

  • 1.Goldberg AS, Tirona RG, Asher LJ, Kim RB, Van Uum SH. Ciprofloxacin and rifampin have opposite effects on levothyroxine absorption. Thyroid 2013 Nov;23(11):1374-8.
  • 2.Cooper JG, Harboe K, Frost SK, Skadberg O. Ciprofloxacin interacts with thyroid replacement therapy. BMJ 2005 Apr 30;330(7498):1002.

Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.