tioguanine at a glance
Medicine class
Cytotoxic purine antimetabolite chemotherapy
Licensed uses
Acute leukaemias, particularly acute myeloid and acute lymphoblastic leukaemia
Administration
Swallow the tablets with water and follow the specialist team's instructions about food
Key monitoring
Blood counts and liver function require close monitoring
What is tioguanine used for?
Specialist uses include:
Licensed treatment of acute leukaemias, especially acute myeloid and acute lymphoblastic leukaemia.
Non-licensed specialist use in selected people with inflammatory bowel disease, particularly after intolerance or inadequate response to conventional thiopurines. Practice varies because of liver-toxicity concerns.
How does tioguanine work?
Tioguanine resembles the natural purine base guanine. Cells convert it into active thioguanine nucleotides, which disrupt purine production and become incorporated into nucleic acids, impairing DNA synthesis and the survival of rapidly dividing cells.
tioguanine preparations and strengths
Tablet
Route: Oral
Strengths: 40 mg
How to take tioguanine
Take tioguanine exactly as directed by the specialist team. Food and vomiting can affect absorption, so do not change your routine independently.
Swallow tablets whole with a glass of water where possible.
If a tablet must be broken for easier swallowing, avoid inhaling powder and wash your hands afterwards.
The score line helps with swallowing; it does not divide the tablet into equal amounts.
Do not crush or otherwise manipulate tablets unless the specialist pharmacy provides specific instructions.
tioguanine side effects
Common or expected effects
- Reduced blood-cell production, causing infection risk, anaemia, bruising or bleeding
- Nausea, vomiting, diarrhoea, mouth soreness or ulcers
- Changes in liver function or other liver injury
- Raised uric acid, which can affect the kidneys
- Increased sensitivity to sunlight
Get urgent medical advice
- Severe infection or marked bone-marrow suppression
- Liver vascular injury, jaundice, fluid retention or signs of portal hypertension
- Severe abdominal pain with vomiting, diarrhoea or fever, which may indicate necrotising colitis
- Severe liver damage
tioguanine in pregnancy
Tioguanine can harm a developing baby and should be avoided during pregnancy where possible, particularly early pregnancy, unless specialist assessment finds that the expected benefit outweighs the risk. Effective contraception is required when either partner is receiving treatment. Rarely, thiopurines have been linked to intrahepatic cholestasis of pregnancy; report intense itching without a rash, nausea or loss of appetite immediately without stopping treatment independently.
tioguanine while breastfeeding
There is insufficient information about passage into breast milk. People receiving tioguanine should not breastfeed; discuss feeding options with the oncology and maternity teams.
tioguanine interactions
The specialist team should review prescribed, pharmacy-bought, herbal and complementary products before treatment.
Live vaccines
Immunosuppression can allow a live vaccine organism to cause infection, so live vaccines are generally avoided during treatment.
Mesalazine, olsalazine and sulfasalazine
These may inhibit TPMT and increase susceptibility to tioguanine toxicity.
Other bone-marrow-suppressing treatments
Other cytotoxic medicines or radiotherapy can add to bone-marrow suppression, requiring specialist review and closer monitoring.
Common questions about tioguanine
Answers are fully visible for fast scanning and source review.
Why is specialist supervision needed?
Tioguanine can substantially suppress bone marrow and damage the liver, so treatment requires expertise, laboratory monitoring and access to supportive care.
Why are blood tests needed?
They can detect falling blood-cell counts, liver injury and other toxicity before or alongside symptoms.
What do TPMT and NUDT15 mean for treatment?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.