Tiopronin

DRUG INFORMATION

  ADULT
    - The recommended initial dosage in adult patients is 800 mg/day.
      Source: US FDA label for tiopronin (TIOPRONIN), section 'dosage and
      administration', retrieved 2026-08-29
    - In clinical studies, the average dosage was about 1,000 mg/day.
      Source: US FDA label for tiopronin (TIOPRONIN), section 'dosage and
      administration', retrieved 2026-08-29
    - ( 2.2 ) 2.1 Recommended Dosage Adults : The recommended initial dosage in adult
      patients is 800 mg/day.
      Source: US FDA label for tiopronin (TIOPRONIN), section 'dosage and
      administration', retrieved 2026-08-29

  CHILD
    - Tiopronin delayed-release tablets are indicated in pediatric patients 9 years of
      age and older with severe homozygous cystinuria, in combination with high fluid
      intake, alkali, and diet modification, for the prevention of cystine stone
      formation who are not responsive to these measures alone. This indication is based
      on safety and efficacy data from a trial in patients 9 years to 68 years of age
      and clinical experience .
      Source: US FDA label for tiopronin (TIOPRONIN), section 'pediatric use', retrieved
      2026-08-29
    - The recommended initial dosage in adult patients is 800 mg/day. In clinical
      studies, the average dosage was about 1,000 mg/day. ( 2.1 ) The recommended
      initial dosage in pediatric patients 9 years of age and older is 15 mg/kg/day.
      Avoid dosages greater than 50 mg/kg per day in pediatric patients .
      Source: US FDA label for tiopronin (TIOPRONIN), section 'dosage and
      administration', retrieved 2026-08-29
    - Pediatric patients receiving greater than 50 mg/kg tiopronin per day may be at
      greater risk [see Dosage and Administration ( 2.1 , 2.3 ), Warnings and
      Precautions ( 5.1 ) and Adverse Reactions ( 6.1 )].
      Source: US FDA label for tiopronin (TIOPRONIN), section 'pediatric use', retrieved
      2026-08-29

  RENAL IMPAIRMENT
    - No kidney-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for tiopronin (TIOPRONIN),
      retrieved 2026-08-29

  HEPATIC IMPAIRMENT
    - No liver-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for tiopronin (TIOPRONIN),
      retrieved 2026-08-29

  PREGNANCY
    - Risk Summary Available published case report data with tiopronin have not
      identified a drug-associated risk for major birth defects, miscarriage, or adverse
      maternal or fetal outcomes.
      Source: US FDA label for tiopronin (TIOPRONIN), section 'pregnancy', retrieved
      2026-08-29
    - Renal stones in pregnancy may result in adverse pregnancy outcomes (see Clinical
      Considerations).
      Source: US FDA label for tiopronin (TIOPRONIN), section 'pregnancy', retrieved
      2026-08-29
    - In animal reproduction studies, there were no adverse developmental outcomes with
      oral administration of tiopronin to pregnant mice and rats during organogenesis at
      doses up to 2 times a 2 grams/day human dose (based on mg/m 2 ).
      Source: US FDA label for tiopronin (TIOPRONIN), section 'pregnancy', retrieved
      2026-08-29

  BREASTFEEDING
    - Lactation: Breastfeeding is not recommended.
      Source: US FDA label for tiopronin (TIOPRONIN), section 'use in specific
      populations', retrieved 2026-08-29
    - Data Animal Data No findings of fetal malformations could be attributed to the
      drug in reproduction studies in mice and rats at doses up to 2 times the highest
      recommended human dose of 2 grams/day (based on mg/m 2 ). 8.2 Lactation Risk
      Summary There are no data on the presence of tiopronin in either human or animal
      milk or on the effects of the breastfed child.
      Source: US FDA label for tiopronin (TIOPRONIN), section 'use in specific
      populations', retrieved 2026-08-29