Prescription medicine
Thioguanine Brand names: Tabloid
Thioguanine (Tabloid) is a prescription medicine with an FDA approval on record since 1966. No generic is listed in FDA's NDC Directory.
- No generic listed
Check it at the source: the thioguanine FDA label on DailyMed (effective January 8, 2025, Waylis Therapeutics LLC); the NDA 12429 record on Drugs@FDA; every thioguanine label on DailyMed.
Highlights of the record
FDA label of January 8, 2025; NDC Directory, Drugs@FDA and Orange Book, October 8, 2026
Used for
From the label: indications and usagea) Acute Nonlymphocytic Leukemias TABLOID brand Thioguanine is indicated for remission induction and remission consolidation treatment of acute nonlymphocytic leukemias.
Forms and strengths
- 40 mg
Tablet.
On the market
- Earliest approval on file
- January 18, 1966 Thioguanine, Waylis Therap; Drugs@FDA’s file, where older or withdrawn approvals can be missing
- Generic approvals
- No generic approved
- Labelers listed (NDC)
- 1 of which 0 under generic applications, 1 under brand applications, repackagers included
Supply and safety
- Pharmacy cost (NADAC)
- Not in the survey
- Shortage (FDA)
- No current entry
- Recalls by its makers (FDA)
- No recall recorded
- FAERS reports
- 2,099 through July 30, 2026
What is thioguanine used for?
From the label: indications and usagea) Acute Nonlymphocytic Leukemias TABLOID brand Thioguanine is indicated for remission induction and remission consolidation treatment of acute nonlymphocytic leukemias. However, it is not recommended for use during maintenance therapy or similar long-term continuous treatments due to the high risk of liver toxicity (see WARNINGS and ADVERSE REACTIONS). The response to this agent depends upon the age of the patient (younger patients faring better than older) and whether thioguanine is used in previously treated or previously untreated patients. […]
Conditions named in the indications of thioguanine's FDA labels, with every medicine labeled for each:
From other thioguanine labelsLeukemia, lymphoma and myeloma: Although thioguanine is one of several agents with activity in the treatment of the chronic phase of chronic myelogenous leukemia, more objective responses are observed with MYLERAN ® (busulfan), and therefore busulfan is usually regarded …
FDA pharmacologic class: Antimetabolite.
Source: FDA drug label (TABLOID), Waylis Therapeutics LLC, effective January 8, 2025 (SPL set 44b0c461-47fb-4106-ba11-6ed85530235c), via openFDA; the full label on DailyMed
Is there a generic for thioguanine (Tabloid)?
No generic thioguanine is approved (Drugs@FDA, October 8, 2026).
- 1966 earliest approval on file
Source: Drugs@FDA, FDA NDC Directory and the Orange Book (openFDA bulk files, October 8, 2026)
What does the thioguanine label say about other medicines?
The thioguanine label names 2 other medicines in its interaction, contraindication or warning sections. The labels of 3 other medicines name thioguanine. The sentences are the labels' own; a label lists what its studies and reports found, not every interaction.
| Medicine named | Section | What the label says |
|---|---|---|
| Mercaptopurine | contraindications | In animals and humans, there is usually complete cross-resistance between PURINETHOL (mercaptopurine) and TABLOID brand Thioguanine. |
| Olsalazine | drug interactions | As there is in vitro evidence that aminosalicylate derivatives (e.g., olsalazine, mesalazine, or sulphasalazine) inhibit the TPMT enzyme, they should be administered with caution to patients receiving concurrent thioguanine therapy (see WARNINGS). |
Other labels that name thioguanine
Source: FDA drug label (TABLOID), Waylis Therapeutics LLC, effective January 8, 2025 (SPL set 44b0c461-47fb-4106-ba11-6ed85530235c), via openFDA; the full label on DailyMed
What do FAERS reports show for thioguanine?
The FDA Adverse Event Reporting System holds 2,099 reports that list thioguanine among the medicines taken, through July 30, 2026, each a report of something that happened, not proof the medicine caused it; 376 are coded as a death and 972 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is.
Reports received each year
The most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026
What else is labeled for the same conditions as thioguanine?
37 other medicines are given the same way (oral) and in the same FDA class as thioguanine or labeled mainly for the same use (leukemia, lymphoma and myeloma), the same class first. Leukemia, lymphoma and myeloma lists all 98 medicines labeled for it, by any route. The first 8 are below. They are listed as records, not as substitutes: whether one can replace another is a prescriber's decision.
| Medicine | Shared indication | Generic labelers (oral) | Pharmacy cost | Shortage |
|---|---|---|---|---|
| Hydroxyurea | Leukemia, lymphoma and myeloma | 10 labelers | $0.184 per capsule 500 mg capsule | No current entry |
| Lenalidomide | Leukemia, lymphoma and myeloma | 18 labelers | n/a | No current entry |
| Dasatinib | Leukemia, lymphoma and myeloma | 14 labelers | $26.46 per tablet 100 mg tablet | No current entry |
| Pomalidomide | Leukemia, lymphoma and myeloma | 11 labelers | n/a | No current entry |
| Imatinib | Leukemia, lymphoma and myeloma | 20 labelers | $0.624 per tablet 100 mg tablet | No current entry |
| Arsenic trioxide | Leukemia, lymphoma and myeloma | none listed | n/a | A presentation being discontinued |
| Nilotinib | Leukemia, lymphoma and myeloma | 6 labelers | n/a | No current entry |
| Cyclophosphamide | Leukemia, lymphoma and myeloma | 4 labelers | $1.67 per capsule 50 mg capsule | No current entry |
Every medicine labeled for the same conditions as thioguanine
Source: FDA drug labels (indications), NDC Directory, NADAC of October 7, 2026, FDA shortages (October 8, 2026)
What next?
- Alternatives to thioguanine
- 37 medicines for the same use
- Other antimetabolites
- the pharmacologic class, with prices and generics
- Thioguanine side effects
- the label's list beside FAERS reports
- Check an interaction
- what two or more labels say about each other