tolazamide (Tolinase brand has been discontinued.)

  • Pharmacy Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.



  • Generally, patients are started on 100 to 250 mg of tolazamide once daily with breakfast or first meal of the day.
  • Start with 100 mg/day for fasting blood sugar <200 mg/dL or 250 mg for fasting blood sugar >200 mg/dL.
  • Use 100 mg/day for patients who are malnourished, underweight, elderly, or those not eating properly.
  • Dosage may be increased by 100-250 mg at weekly intervals.
  • The maximum daily dose is 500 mg orally twice daily (1000mg/day).

The safety and efficacy of tolazamide has not been established in pediatric patients. No specific dose adjustments are recommended in patients with kidney or liver disease.


  • Coadministration of tolazamide with quinolone antibiotics may cause abnormal changes in blood glucose. Therefore, blood glucose must be closely monitored if these agents must be used together.
  • Tolazamide may increase blood levels of methotrexate (Rheumatrex, Trexall) by interfering with the binding of methotrexate to blood proteins.
  • Anti-retroviral protease inhibitors, a type of anti-HIV medication, may decrease the effectiveness of tolazamide and consequently worsen blood glucose control.


  • Tolazamide has not been adequately evaluated in pregnant women. Due to the lack of conclusive safety data, tolazamide should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus. Tolazamide is classified as FDA pregnancy risk category C.
  • It is not known if tolazamide is excreted in breast milk. Due to the potential risk for hypoglycemia (low blood glucose) in the nursing infant, use of tolazamide is not recommended in nursing mothers.

PREPARATIONS: Oral tablets: 100, 250, and 500 mg

STORAGE: Tablets should be stored at room temperature, between 15 C and 30 C (59 F to 86 F).

How does tolazamide work?

  • Tolazamide is an oral medication used to treat high blood glucose in patients with type 2 diabetes mellitus. It is a first generation sulfonylurea used in combination with exercise and dietary modifications to lower blood glucose in patients. Tolazamide stimulates the release of insulin from the pancreatic beta cells. Insulin is responsible for regulating how the body uses and stores glucose. It also reduces the production of glucose from the liver and increases the sensitivity of cells throughout the body to insulin. By increasing muslin sensitivity, the cells remove more glucose from the blood.
  • Tolazamide was approved by the FDA in 1965.

REFERENCE: FDA Prescribing Information

Medically Reviewed by a Doctor on 9/23/2016

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