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Tiopronin 100 mg Tablet, Delayed Release, 300-count — NDC 13668-0691-03 package photo
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Tiopronin 100 mg Tablet, Delayed Release, 300-count — NDC 13668-691-03 (Billing 13668-0691-03)

by Torrent Pharmaceuticals Limited · 300 TABLET, DELAYED RELEASE in 1 BOTTLE

This is a package of 300 tablets of Tiopronin 100 mg Tablet, Delayed Release from Torrent Pharmaceuticals Limited, marketed since Jan 2024 and currently FDA-listed. It is this product's only package size.

NDC 13668-0691-03
🏷️ FDA NDC (as labeled) 13668-691-03 billing pads the product segment with a zero
Rx only Generic On market Non-controlled ⇄ Compare with another NDC
🗂️ FDA directory synced Oct 1, 2026 · this listing last changed Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

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Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

Identity & classification

Regulatory identifiers FDA, NLM and CMS codes for this package

FDA NDC (as labeled) 13668-691-03
Product NDC 13668-691
11-digit billing NDC 13668069103
NCPDP billing unit EA — each (per item)
RxCUI 2178075, 2178079
UNII C5W04GO61S
UPC 0313668692907, 0313668691030
Application # ANDA216990
SPL Set ID ad750031-08ec-4d92-af2d-97a80c454e14
Established class (EPC) Reducing and Complexing Thiol
Mechanism of action Cystine Disulfide Reduction
Chemical class N-substituted Glycines
DEA schedule Non-controlled
Marketing category ANDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2024-01-30
Route ORAL
Dosage form TABLET, DELAYED RELEASE
Substance TIOPRONIN
TE code (Orange Book) AB · RLD · RS

Drug-database identifiers Medi-Span GPI and First Databank GCN / HICL / AHFS classification

GPI-14 56600050000620
GCN Seq No 079977
GCN 46629
HICL code 003714
Ingredient (HICL) Tiopronin
HIC1 code R
Therapeutic class — broad (HIC1) Kidney/Urinary Tract
HIC2 code R4
Therapeutic class — intermediate (HIC2) Agents Affecting Renal Calculi
HIC3 code R4A
Therapeutic class — specific (HIC3) Kidney Stone Agents
AHFS code 92:92.00.00
AHFS class Other Miscellaneous Therapeutic Agents
FDB label name TIOPRONIN DR 100 MG TABLET
FDB brand name Tiopronin
Legend status F — Federal legend — prescription drug or device
Quick answers
  • GSN (GCN sequence number): 079977
  • GCN: 46629
  • GPI-14 (Medi-Span): 56600050000620
  • HICL (First Databank): 003714
  • AHFS class code: 92:92.00.00
  • RxCUI (RxNorm): 2178075
Why two NDCs? The FDA registers this code as 13668-691-03 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 13668-0691-03. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

RxNorm drug class

This medicine belongs to the Reducing and Complexing Thiol class.

Pharmacologic class Reducing and Complexing Thiol
Drug family (ATC) Other urologicals
How it works Cystine Disulfide Reduction
Where does this data come from?
Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

Clinical

Label name TIOPRONIN DR 100 MG TABLET Ingredient Tiopronin
📗 Our plain-language guide HelloPharmacist
  • You have a condition called cystinuria, where your kidneys release too much cystine — a naturally occurring substance — into your urine. When cystine builds up, it forms painful ki...
  • What exactly does tiopronin do, and why do I need it?
  • Yes — and it depends on which product you have. If you're taking Thiola tablets or regular Tiopronin tablets, take them at least an hour before eating or two hours after a meal. If...
  • Does it matter when I take it with food?
📖 Read our full Tiopronin guide →
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer eachPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · Q2 2026 $20.80 $6,239.31 / 300 tablets
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

Packaging — all sizes for this product

Package NDCDescription Marketing startMarketing endStatus
13668-0691-03 You're viewing this Main listing 300 TABLET, DELAYED RELEASE in 1 BOTTLE 2024-01-30 — Active

Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Thiola EC 100 mg 00178-0902-01 Mission 300 tablets — AB FDA listed —
Tiopronin 100 mg 00254-3034-30 Par 300 tablets — AB FDA listed —
Tiopronin 100 mg 00480-9227-55 Teva 300 tablets — AB FDA listed —
Tiopronin 100 mgthis 13668-0691-03 Torrent 300 tablets — AB FDA listed —
Tiopronin 100 mg 44523-0054-01 BioComp 300 tablets — AB FDA listed —
Venxxiva 100 mg 70709-0121-30 Cycle 300 tablets — AB FDA listed —
About this product: this is a generic version of the medicine. FDA equivalence ratings are shown when available, and other versions are listed above, least expensive first.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

Availability & generic status

🏛️
2024
On the market since
Jan 2024
📍
2026
Currently FDA-listed
2 years listed
🔓
·
Generic on the market
this product is a generic
✅This is a generic drug

This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.

Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

What it looks like

Color White
ShapeRound
Imprint3A
Size11 mm
ScoringNot scored
One label can cover several strengths, so colors may be combined — always confirm a loose pill against the dispensed prescription label or a pharmacist.
Where does this data come from?
Physical description (imprint, shape, color, scoring, coating) from this product’s FDA Structured Product Labeling (SPL), mirrored from DailyMed / openFDA.

Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

  • UNII 2165RE0K14
    A plant-based thickener made from cellulose that helps control how quickly the medicine dissolves and releases its active ingredient. It also binds ingredients together and improves the tablet's texture and handling during manufacturing.
  • UNII 9XZ8H6N6OH
    A plant-based cellulose derivative used as a binder to hold tablet ingredients together, a thickener in liquids, and a coating agent to control how fast the medicine dissolves.
  • UNII 3NXW29V3WO
    Hypromellose is a plant-based thickener made from cellulose. It's used in medicines as a binder to hold ingredients together, a coating for tablets, and a thickener for liquids.
  • UNII EWQ57Q8I5X
    Lactose monohydrate is a natural sugar derived from milk. It serves as a filler and binder in tablets and capsules, helping create the proper size, texture, and consistency of the medicine.
  • UNII 70097M6I30
    Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
  • UNII NX76LV5T8J
    A synthetic plastic polymer made from methacrylic acid and ethyl acrylate. It's used as a coating or binder to control how and where the medicine dissolves in your digestive system.
  • UNII 7SEV7J4R1U
    A powder made from a naturally occurring mineral. In medicines, talc works as a glidant and anti-caking agent, helping tablets and capsules flow smoothly during manufacturing and preventing clumping.
  • UNII 8Z96QXD6UM
    Triethyl citrate is a clear liquid derived from citric acid. It acts as a plasticizer and solvent in tablet coatings and film formulations, helping the coating remain flexible and adhere properly to the medicine.

8 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?
Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

Manufacturer & labeler

LabelerTorrent Pharmaceuticals Limited
Application holderTORRENT PHARMACEUTICALS LTD
FDA applicationANDA216990 (ANDA)
Labeler code13668
First marketedJan 2024
Product typeHuman Prescription Drug
Portfolio182 products on file
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Very long sections are excerpted here and marked; the full text is on DailyMed (linked in the sources below). Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage ⏱️ Dosage and Administration 💊 Dosage Forms and Strengths ⛔ Contraindications ⚠️ Warnings and Cautions 🤒 Adverse Reactions 🔄 Drug Interactions 👥 Use in Specific Populations 🤰 Pregnancy 🧒 Pediatric Use 🧓 Geriatric Use 🆘 Overdosage 🧬 Clinical Pharmacology 🧬 Mechanism of Action 📦 How Supplied / Storage and Handling 📋 Description 💬 Information for Patients 🧬 Pharmacokinetics 🧬 Pharmacodynamics 🧪 Nonclinical Toxicology 📄 Carcinogenesis, Mutagenesis, Impairment of Fertility 📄 Package Label / Principal Display Panel
🎯 Indications and Usage 135 words ▾

1 INDICATIONS AND USAGE Tiopronin delayed-release tablets are indicated, in combination with high fluid intake, alkali, and diet modification, for the prevention of cystine stone formation in adults and pediatric patients 9 years of age and older with severe homozygous cystinuria, who are not responsive to these measures alone. Additional pediatric use information is approved for Mission Pharmacal Company’s Thiola EC (tiopronin delayed-release) tablets. However, due to Mission Pharmacal Company’s marketing exclusivity rights, this drug product is not labeled with that information.

Tiopronin delayed-release tablets are a reducing and complexing thiol indicated, in combination with high fluid intake, alkali, and diet modification, for the prevention of cystine stone formation in adults and pediatric patients 9 years of age and older with severe homozygous cystinuria, who are not responsive to these measures alone. ( 1 )

⏱️ Dosage and Administration ~1 min read ▾

2 DOSAGE AND ADMINISTRATION 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. ( 5.1 , 8.4 ) Measure urinary cystine 1 month after initiation of tiopronin delayed-release tablets and every 3 months thereafter ( 2.3 ) Administer tiopronin delayed-release tablets in 3 divided doses at the same times each day, without food. ( 2.1 )

2.1Recommended Dosage Adults : The recommended initial dosage in adult patients is 800 mg/day. In clinical studies, the average dosage was about 1,000 mg/day. Pediatrics : 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 [see Warnings and Precautions ( 5.1 ), Use in Specific Populations ( 8.4 )] . Administer tiopronin delayed-release tablets in 3 divided doses at the same times each day, without food. Consider starting tiopronin delayed-release tablets at a lower dosage in patients with history of severe toxicity to d-penicillamine.

Additional pediatric use information is approved for Mission Pharmacal Company’s Thiola EC (tiopronin delayed-release) tablets. However, due to Mission Pharmacal Company’s marketing exclusivity rights, this drug product is not labeled with that information.

2.3Monitoring Measure urinary cystine 1 month after starting tiopronin delayed-release tablets and every 3 months thereafter. Adjust tiopronin delayed-release tablets dosage to maintain urinary cystine concentration less than 250 mg/L. Assess for proteinuria before treatment and every 3 to 6 months during treatment [see Warnings and Precautions ( 5.1 )] .

Discontinue tiopronin delayed-release tablets in patients who develop proteinuria, and monitor urinary protein and renal function. Consider restarting tiopronin delayed-release tablets treatment at a lower dosage after resolution of proteinuria.

💊 Dosage Forms and Strengths 76 words ▾

3 DOSAGE FORMS AND STRENGTHS Tablets for oral use: 100 mg tablets: White to off-white, round shaped, enteric coated tablets imprinted with "1A" with black ink on one side and plain on other side, free from physical defects. 300 mg tablets: White to off-white, round shaped, enteric coated tablets imprinted with "3A" with black ink on one side and plain on other side, free from physical defects. Tablets: 100 mg and 300 mg ( 3 )

⛔ Contraindications 42 words ▾

4 CONTRAINDICATIONS Tiopronin delayed-release tablets are contraindicated in patients with hypersensitivity to tiopronin or any other components of tiopronin delayed-release tablets [see Warnings and Precautions ( 5.2 )] . Hypersensitivity to tiopronin or any component of tiopronin delayed-release tablets ( 4 )

⚠️ Warnings and Cautions 154 words ▾

5 WARNINGS AND PRECAUTIONS Proteinuria, including nephrotic syndrome, and membranous nephropathy, has been reported with tiopronin use. Pediatric patients receiving greater than 50 mg/kg of tiopronin per day may be at increased risk for proteinuria. ( 2.1 , 5.1 , 8.4 ) Hypersensitivity reactions have been reported during tiopronin treatment. ( 4 , 5.2 )

5.1Proteinuria Proteinuria, including nephrotic syndrome, and membranous nephropathy, have been reported with tiopronin use. Pediatric patients receiving greater than 50 mg/kg of tiopronin per day may be at increased risk for proteinuria. [see Dosage and Administration ( 2.3 ), Adverse Reactions ( 6.1 , 6.2 ) Use in Specific Populations ( 8.4 )] . Monitor patients for the development of proteinuria and discontinue therapy in patients who develop proteinuria [see Dosage and Administration ( 2.3 )] .

5.2Hypersensitivity Reactions Hypersensitivity reactions (drug fever, rash, fever, arthralgia and lymphadenopathy) have been reported [see Contraindications ( 4 )] .

🤒 Adverse Reactions ~3 min read ▾

6 ADVERSE REACTIONS The following adverse reactions are discussed in greater detail in other sections of the labeling: Proteinuria [see Warnings and Precautions ( 5.1 )] Hypersensitivity [see Warnings and Precautions ( 5.2 )] Most common adverse reactions (≥10%) are nausea, diarrhea or soft stools, oral ulcers, rash, fatigue, fever, arthralgia, proteinuria, and emesis. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Torrent Pharma Inc. at 1-800-912-9561 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, the adverse reaction rates observed in the clinical trials of the drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Adverse reactions occurring at an incidence of ≥5% in an uncontrolled trial in 66 patients with cystinuria age 9 to 68 years are shown in the table below. Patients in group 1 had previously been treated with d-penicillamine; those in group 2 had not.

Of those patients who had stopped taking d-penicillamine due to toxicity (34 out of 49 patients in group 1), 22 were able to continue treatment with tiopronin. In those without prior history of d-penicillamine treatment, 6% developed reactions of sufficient severity to require tiopronin withdrawal. Table 1 presents adverse reactions ≥5% in either treatment group occurring in this trial.

Table 1: Adverse Reactions Occurring in One or More Patients System Organ Class Adverse Reaction Group 1 Previously treated with d-penicillamine (N = 49) Group 2 Naïve to d-penicillamine (N = 17) Blood and Lymphatic System Disorders anemia 1 (2%) 1 (6%) Gastrointestinal Disorders nausea 12 (25%) 2 (12%) emesis 5 (10%) – diarrhea/soft stools 9 (18%) 1 (6%) abdominal pain – 1 (6%) oral ulcers 6 (12%) 3 (18%) General Disorders and Administration Site Conditions fever 4 (8%) – weakness 2 (4%) 2 (12%) fatigue 7 (14%) – peripheral (edema) 3 (6%) 1 (6%) chest pain – 1 (6%) Metabolism and Nutrition Disorders anorexia 4 (8%) – Musculoskeletal and Connective Tissue Disorders arthralgia – 2 (12%) Renal and Urinary Disorders proteinuria 5 (10%) 1 (6%) impotence – 1 (6%) Respiratory, Thoracic and Mediastinal Disorders cough – 1 (6%) Skin and Subcutaneous Tissue Disorders rash 7 (14%) 2 (12%) ecchymosis 3 (6%) – pruritus 2 (4%) 1 (6%) urticaria 4 (8%) – skin wrinkling 3 (6%) 1 (6%) Taste Disturbance A reduction in taste perception may develop.

It is believed to be the result of chelation of trace metals by tiopronin. Hypogeusia is often self-limited.

6.2Postmarketing Experience Adverse reactions have been reported from the literature, as well as during post-approval use of tiopronin. Because the post-approval reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to tiopronin exposure. Adverse reactions reported during the postmarketing use of tiopronin are listed by body system in Table 2 .

Table 2: Adverse Reactions Reported for Tiopronin Pharmacovigilance by System Organ Class and Preferred Term System Organ Class Preferred Term Cardiac Disorders congestive heart failure Ear and Labyrinth Disorder vertigo Gastrointestinal Disorders abdominal discomfort; abdominal distension; abdominal pain; chapped lips; diarrhea; dry mouth; dyspepsia; eructation; flatulence; gastrointestinal disorder; gastroesophageal reflux disease; nausea; vomiting; jaundice; liver transaminitis General Disorders and Administration Site Conditions asthenia; chest pain; fatigue; malaise; pain; peripheral swelling; pyrexia; swelling Investigations glomerular filtration rate decreased; weight increased Metabolism and Nutrition Disorders decreased appetite; dehydration; hypophagia Musculoskeletal and Connective Tissue Disorders arthralgia; back pain; flank pain; joint swelling; limb discomfort; musculoskeletal discomfort; myalgia;… [Excerpted — this section continues on DailyMed.]

🔄 Drug Interactions 56 words ▾

7 DRUG INTERACTIONS

7.1Alcohol Tiopronin is released faster from tiopronin delayed-release tablets in the presence of alcohol and the risk for adverse events associated with tiopronin delayed-release tablets when taken with alcohol is unknown. Avoid alcohol consumption 2 hours before and 3 hours after taking tiopronin delayed-release tablets [see Clinical Pharmacology ( 12.3 )] .

👥 Use in Specific Populations ~3 min read ▾

8 USE IN SPECIFIC POPULATIONS Lactation: Breastfeeding is not recommended. ( 8.2 ) Geriatric: Choose dose carefully and monitor renal function in the elderly. ( 8.5 ) Additional pediatric use information is approved for Mission Pharmacal Company’s Thiola EC (tiopronin delayed-release) tablets. However, due to Mission Pharmacal Company’s marketing exclusivity rights, this drug product is not labeled with that information.

8.1Pregnancy 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. Renal stones in pregnancy may result in adverse pregnancy outcomes (see Clinical Considerations ) . 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 ).

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies are 2% to 4% and 15% to 20%, respectively.

Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Renal stones in pregnancy may increase the risk of adverse pregnancy outcomes, such as preterm birth and low birth weight. 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 ).

8.2Lactation 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. A published study suggests that tiopronin may suppress milk production. Because of the potential for serious adverse reactions, including nephrotic syndrome, advise patients that breastfeeding is not recommended during treatment with tiopronin delayed-release tablets.

8.4Pediatric Use 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. Proteinuria, including nephrotic syndrome, has been reported in pediatric patients.

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 )] . Tiopronin delayed-release tablets are not approved for use in pediatric patients weighing less than 20 kg or in pediatric patients unable to swallow tablets [see Dosage and Administration ( 2.1 )] . Additional pediatric use information is approved for Mission Pharmacal Company’s Thiola EC (tiopronin delayed-release) tablets.

However, due to Mission Pharmacal Company’s marketing exclusivity rights, this drug product is not labeled with that information.

8.5Geriatric Use This drug is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

🤰 Pregnancy 206 words ▾

8.1Pregnancy 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. Renal stones in pregnancy may result in adverse pregnancy outcomes (see Clinical Considerations ) . 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 ).

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies are 2% to 4% and 15% to 20%, respectively.

Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Renal stones in pregnancy may increase the risk of adverse pregnancy outcomes, such as preterm birth and low birth weight. 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 ).

🧒 Pediatric Use 182 words ▾

8.4Pediatric Use 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. Proteinuria, including nephrotic syndrome, has been reported in pediatric patients.

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 )] . Tiopronin delayed-release tablets are not approved for use in pediatric patients weighing less than 20 kg or in pediatric patients unable to swallow tablets [see Dosage and Administration ( 2.1 )] . Additional pediatric use information is approved for Mission Pharmacal Company’s Thiola EC (tiopronin delayed-release) tablets.

However, due to Mission Pharmacal Company’s marketing exclusivity rights, this drug product is not labeled with that information.

🧓 Geriatric Use 59 words ▾

8.5Geriatric Use This drug is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

🆘 Overdosage 10 words ▾

10 OVERDOSAGE There is no information on overdosage with tiopronin.

🧬 Clinical Pharmacology ~1 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action The goal of therapy is to reduce urinary cystine concentration below its solubility limit. Tiopronin is an active reducing agent which undergoes thiol-disulfide exchange with cystine to form a mixed disulfide of tiopronin-cysteine. From this reaction, a water-soluble mixed disulfide is formed and the amount of sparingly soluble cystine is reduced.

12.2Pharmacodynamics The decrement in urinary cystine produced by tiopronin is generally proportional to the dose. A reduction in urinary cystine of 250 to 350 mg/day at tiopronin dosage of 1 g/day, and a decline of approximately 500 mg/day at a dosage of 2 g/day, might be expected. Tiopronin has a rapid onset and offset of action, showing a fall in cystine excretion on the first day of administration and a rise on the first day of drug withdrawal.

12.3Pharmacokinetics Absorption Tiopronin Delayed-Release Tablets When tiopronin IR and tiopronin delayed-release tablets single doses were given to fasted healthy subjects, the median time to peak plasma levels (T max ) was 1 (range: 0.5 to 2.1) and 3 (range: 1.0 to 6.0) hours, respectively. The peak exposure (C max ) and total exposure (AUC 0-t ) of tiopronin from tiopronin delayed-release tablets were decreased by 22% and 7% respectively compared to tiopronin IR tablets. Elimination Excretion When tiopronin is given orally, up to 48% of dose appears in urine during the first 4 hours and up to 78% by 72 hours.

Drug Interactions Alcohol An in vitro dissolution study was conducted to evaluate the impact of alcohol (5, 10, 20, and 40%) on the dose dumping of tiopronin delayed- release tablets. The study results showed that the addition of alcohol to the dissolution media increases the dissolution rate of tiopronin delayed- release tablets in the acidic media of 0.1N HCl [see Drug Interactions ( 7.1 )] .

🧬 Mechanism of Action 55 words ▾

12.1Mechanism of Action The goal of therapy is to reduce urinary cystine concentration below its solubility limit. Tiopronin is an active reducing agent which undergoes thiol-disulfide exchange with cystine to form a mixed disulfide of tiopronin-cysteine. From this reaction, a water-soluble mixed disulfide is formed and the amount of sparingly soluble cystine is reduced.

📦 How Supplied / Storage and Handling 96 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING 100 mg delayed-release, white to off-white, round shaped, enteric-coated tablets imprinted with "1A" with black ink on one side and plain on other side, free from physical defects. Bottles of 300 with child-resistant closure, NDC 13668-691-03. 300 mg delayed-release, white to off-white, round shaped, enteric-coated tablets imprinted with "3A" with black ink on one side and plain on other side, free from physical defects.

Bottles of 90 with child-resistant closure, NDC 13668-692-90. Store at 25°C (77°F); excursions permitted between 15C° and 30°C (59°F and 86°F) [see USP Controlled Room Temperature] .

📋 Description 123 words ▾

11 DESCRIPTION Tiopronin delayed-release tablets are a reducing and cystine-binding thiol drug (CBTD) for oral use. Tiopronin is N‑(2‑Mercaptopropionyl) glycine and has the following structure: Tiopronin has the empirical formula C 5 H 9 NO 3 S and a molecular weight of 163.19. In this drug product tiopronin exists as a dl racemic mixture.

Tiopronin is a white to off-white color crystalline powder, which is freely soluble in water. Each tiopronin delayed-release tablet contains 100 or 300 mg of tiopronin. The inactive ingredients in tiopronin delayed-release tablets include lactose monohydrate, low substitute hydroxypropyl cellulose, hydroxypropyl cellulose, magnesium stearate, hypromellose 2910, methacrylic acid: ethyl acrylate copolymer (Eudragit L 100-55), talc, triethyl citrate.

The imprinting ink contains shellac, ferrosoferric oxide and propylene glycol. structural formula

💬 Information for Patients 47 words ▾

17 PATIENT COUNSELING INFORMATION Lactation Advise women that breastfeeding is not recommended during treatment with tiopronin delayed-release tablets [see Use in Specific Populations ( 8.2 )] . Manufactured for: Torrent Pharmaceuticals Limited, India Distributed by: Torrent Pharma Inc., Basking Ridge, NJ 07920 8088451 Revised: June 2023 logo

🧬 Pharmacokinetics 168 words ▾

12.3Pharmacokinetics Absorption Tiopronin Delayed-Release Tablets When tiopronin IR and tiopronin delayed-release tablets single doses were given to fasted healthy subjects, the median time to peak plasma levels (T max ) was 1 (range: 0.5 to 2.1) and 3 (range: 1.0 to 6.0) hours, respectively. The peak exposure (C max ) and total exposure (AUC 0-t ) of tiopronin from tiopronin delayed-release tablets were decreased by 22% and 7% respectively compared to tiopronin IR tablets. Elimination Excretion When tiopronin is given orally, up to 48% of dose appears in urine during the first 4 hours and up to 78% by 72 hours.

Drug Interactions Alcohol An in vitro dissolution study was conducted to evaluate the impact of alcohol (5, 10, 20, and 40%) on the dose dumping of tiopronin delayed- release tablets. The study results showed that the addition of alcohol to the dissolution media increases the dissolution rate of tiopronin delayed- release tablets in the acidic media of 0.1N HCl [see Drug Interactions ( 7.1 )] .

🧬 Pharmacodynamics 79 words ▾

12.2Pharmacodynamics The decrement in urinary cystine produced by tiopronin is generally proportional to the dose. A reduction in urinary cystine of 250 to 350 mg/day at tiopronin dosage of 1 g/day, and a decline of approximately 500 mg/day at a dosage of 2 g/day, might be expected. Tiopronin has a rapid onset and offset of action, showing a fall in cystine excretion on the first day of administration and a rise on the first day of drug withdrawal.

🧪 Nonclinical Toxicology 99 words ▾

13 NONCLINICAL TOXICOLOGY

13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenesis Long-term carcinogenicity studies in animals have not been performed. Mutagenesis Tiopronin was not genotoxic in the chromosomal aberration, sister chromatid exchange, and in vivo micronucleus assays. Impairment of Fertility High doses of tiopronin in experimental animals have been shown to interfere with maintenance of pregnancy and viability of the fetus.

In 2 published male fertility studies in rats, tiopronin at 20 mg/kg/day intramuscular (IM) for 60 days induced reductions in testis, epididymis, vas deferens, and accessory sex glands weights and in the count and motility of cauda epididymal sperm.

📄 Carcinogenesis, Mutagenesis, Impairment of Fertility 96 words ▾

13.1Carcinogenesis, Mutagenesis, Impairment of Fertility Carcinogenesis Long-term carcinogenicity studies in animals have not been performed. Mutagenesis Tiopronin was not genotoxic in the chromosomal aberration, sister chromatid exchange, and in vivo micronucleus assays. Impairment of Fertility High doses of tiopronin in experimental animals have been shown to interfere with maintenance of pregnancy and viability of the fetus.

In 2 published male fertility studies in rats, tiopronin at 20 mg/kg/day intramuscular (IM) for 60 days induced reductions in testis, epididymis, vas deferens, and accessory sex glands weights and in the count and motility of cauda epididymal sperm.

📄 Package Label / Principal Display Panel 17 words ▾

PRINCIPAL DISPLAY PANEL 100 mg - 300 Tablets 300 mg - 90 Tablets image description image description

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗

Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Tiopronin — the program that covers self-administered drugs. 3 manufacturers.
⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Tiopronin. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.
Period
Total Part D spend
$441.5K
Claims incl. refills
99
Beneficiaries
42
Spend / beneficiary
$10,511.18
Spend / claim
$4,459.29
Trend by period
💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for Tiopronin — the ingredient across all brands.

Top reported reactions

Nausea194
Rash129
Fatigue121
Pain118
Pyrexia116
Nephrolithiasis92
Arthralgia85

Age at onset

Child1
Adolescent5
Adult83
Elderly25

Reporter sex

2,449 reports

Serious outcomes

Hospitalization308
Death88
Life-threatening42
Disabling8
Reports over time (by year) — tap or hover for the count & year
2019 2021 2023 2026 215 0
Most recent year is provisional (FAERS lags ~3 months).
Where does this data come from?
Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

About this NDC listing & data coverage

Finished prescription product
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos ✓ Available
Inactive ingredients (structured) ✓ Available
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data ✓ Available
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The form printed on the packaging and shown on DailyMed is the one the FDA registered. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero and the dashes are dropped. The Identity section at the top of this page lists each form of this code.
Is this package still being marketed?
Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by Torrent Pharmaceuticals Limited. Listing status can change — the directory data on this page refreshes weekly.
Who lists this product with the FDA?
Torrent Pharmaceuticals Limited is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.
← 13668-0682-12 · Torrent 13668-0692-90 · Torrent →
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.