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Labeling for this product contains a bolded warning at the BEGINNING of the package insert THAT IS NOT BOXED.

Do Not Interchange

  • Do not interchange Zaroxolyn tablets and other formulations of metolazone that share its slow and incomplete bioavailability and are NOT therapeutically equivalent at the same doses to Mykrox tablets, a more rapidly available and completely bioavailable metolazone product.
  • Formulations bioequivalent to Zaroxolyn and formulations bioequivalent to Mykrox should NOT be interchanged for one another.

Patient Counseling Information

Package Inserts


Additional Information

Updated January 2018