Welcome back!

Continue where you left off.

Text Size :
Medications Banner.png

TS-ONE

TS-ONE is usually used to treat stomach cancer and pancreas cancer.
  • Article last reviewed 21 January 2026
  • 12 mins read

What is this medication for?

This medication is also known as Tegafur-Oteracil-Gimeracil Capsules. 
TS-ONE is usually used to treat stomach cancer and pancreas cancer.

How should I take or use this medication?

  • Take TS-ONE two times a day, after food. Take the exact number of capsules and follow the dosing schedule instructed by your doctor.
    • Swallow the tablet/capsule whole.
    • Do not open, chew or crush the capsule.
    • Inform your doctor or pharmacist if you have difficulty swallowing.
    • Special handling of the medication is needed.
      • Try not to touch the medication with your bare hands. Use the medication cup provided. Wash your hands after handling the medication. 

What should I do if I forget to take or use this medication?

  • If you forget to take a dose, skip the missed dose, and take it at the next scheduled time. Do not take two doses to make up for the missed dose.
  • If you vomit out a dose of TS-ONE, do not take another dose to make up for it. Take your next dose at the usual time. 

What precautions should I take when taking or using this medication?

  • Inform your healthcare professional if:
    • You are allergic to this medication or any of the other ingredients of this medication.
    • You are taking any other medications (e.g. warfarin, phenytoin), including supplements, traditional medications and herbal remedies.
    • You have any other medical conditions.
    • You are going to receive any vaccination or surgery, including dental surgery.
    • You have any plans to start a family in the future.
      • TS-ONE may have an anti-fertility effect, which could be irreversible. You should discuss fertility preservation options with your doctor before starting treatment.
  • You should not breastfeed during treatment.
  • You should not become pregnant during treatment. You should use an effective birth control method during treatment and for at least 6 months after stopping TS-ONE.
  • If you have a partner who could become pregnant, you should use an effective birth control method during treatment and for at least 6 months after stopping TS-ONE.

What are some common side effects of this medication? ​

The table below will list some of the common side effects as well as the rare but serious side effects.

Side EffectManagement
Decrease in white blood cell count. This may increase your chances of getting an infection..
 
  • To reduce risk of infection:
    • Maintain good hand hygiene. Wash your hands before handling food and after using the toilet.
    • Avoid crowds and do not go near people who are sick. Wear a mask if necessary.
    • Eat freshly cooked and well-cooked food. Avoid raw meats, vegetables and eggs, or half-cooked or uncooked food.
  • Proceed to the A&E department immediately if you have any signs of infection such as fever of 38ºC and above, chills, bad sore throat, pain when you pass urine or have mouth sores or wounds that do not heal.
    • Avoid taking Paracetamol to relieve fever as this may mask your fever and delay treatment of the infection
Decrease in platelet count. Low platelet levels can increase your chance of bleeding. 
  • To reduce risk of bleeding:
    • Be careful when using sharp objects such as scissors or knives.
    • Brush your teeth gently with a soft bristle toothbrush to prevent gum bleeding.
    • Try not to bruise, cut or knock yourself. Apply direct pressure to any cuts or wounds to help stop bleeding.
  • Proceed to the A&E department immediately if you have:
    • Bruising without a cause or bruises that get larger in size
    • Black, sticky stools
    • Blood in the urine
    • Coughing out blood or vomit that looks like coffee grounds
    • Bleeding which does not stop
       
Diarrhoea (loose and frequent stools)
  • Drink plenty of clear fluids (at least 2 litres or 8 cups every day).
  • Eat food that is gentler on the stomach such as porridge or soup.
  • Avoid milk, dairy products, high-fibre food and oily or spicy food.
  • Your doctor may prescribe medications to help relieve diarrhoea. Take these as instructed.
  • Proceed to the A&E Department immediately if you have very bad diarrhoea (for example increase in bowel movement of more than 4 times per day) that does not improve even after taking anti-diarrhoeal medications.
Nausea or vomiting
  • Take small and frequent meals.
  • Avoid foods / smells that may make you feel nauseous, such as oily, fried or strong-smelling food.
  • Avoid tight-fitting clothes around the waist.
  • Your doctor may prescribe medications to help relieve or prevent nausea or vomiting. Take these as instructed.

Mouth ulcers or sores. 

  • This can occur on the tongue, the sides of the mouth or in the throat and can lead to an infection.
     
  • Rinse your mouth regularly with an alcohol-free mouthwash or salt water to help reduce the chances of infection.
  • Brush your teeth gently after eating and at bedtime with a soft bristle toothbrush.
  • Rinse and brush your dentures after eating and soak them in denture solution overnight.
  • Avoid spicy food and take soft foods e.g. porridge.
  • Your doctor may prescribe medications to help relieve or prevent the mouth sores. Use these as instructed.
  • Inform your doctor if you are eating or drinking a lot lesser because of mouth pain.
Hyperpigmentation
  • This condition involves dark spots or patches of the skin which are caused by an excessive production of the pigment melanin and appear darker than usual.
Heart problems  
  • Proceed to the A&E department immediately if you experience signs of heart problems such as shortness of breath, difficulty breathing, chest pain, fast heartbeat, or sudden swelling of legs.
Liver problems

Proceed to the A&E department immediately if you experience any:

  • Dark or tea-coloured urine
  • Pale or light-coloured stools
  • Yellowing of skin or eyes
  • Nausea, vomiting with loss of appetite
  • Severe abdominal pain
     

Symptoms of drug allergy including one or more of the following:

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body
     
  • Inform your doctor if you experience eye pain, swelling, redness, blurred vision, and/or sensitivity to light or other changes.

It is normal to experience some side effects from TS-ONE. As discussed with your doctor, taking TS-ONE will help your condition. Do not stop taking TS-ONE without checking with your doctor.

What food or medication should I avoid when I take or use this medication?

Avoid eating any raw, uncooked or under-cooked food as your immunity is weakened.  

How should I store this medication?

Store in a cool and dry place, away from direct sunlight. Keep this medication away from children.  

How do I throw away this medication safely? ​

Pack the medication into a bag and bring it back to the pharmacy where you received the medication from.  

What else should I know about this medication? 

Tips to help manage your condition while you are on TS-ONE

ExerciseLight exercise is recommended as it helps to improve mobility, balance, and even emotional well-being. Avoid strenuous exercise, and rest when you are feeling tired.
Adequate hydrationHave plenty of hydration with 2 to 3 litres of fluids per day unless you have been informed by your doctor to limit how much fluids you can drink. This will decrease your chances of getting constipation and prevent dehydration.
Medical and dental treatmentIf you need to go into hospital for any reason other than cancer, always inform the doctors and nurses that you are receiving anti-cancer treatment.
Talk to your cancer doctor if you think you need dental treatment. Always inform your dentist that you are receiving anti-cancer treatment.
Seek support if you feel overwhelmedIt is normal to feel fearful or worried about your condition.
Do not be afraid to share  your concerns with your healthcare team or loved ones.
There may be resources and support available to help you.
 

Disclaimer

Please take note that the above is not a complete list of all possible side-effects. If you have any concerns about your medication or if you have other side-effects that you think are caused by this medication, please consult your doctor or pharmacist. If you take more than the recommended dose, please seek medical advice immediately. The information provided on this page does not replace information from your healthcare professional. Please consult your healthcare professional for more information.

This article is jointly developed by members of the National Medication Information workgroup. The workgroup consists of cluster partners (NHG Health, National University Health System and SingHealth), community pharmacies (Guardian, Unity and Watsons) and Pharmaceutical Society of Singapore. The content does not reflect drug availability and supply information in pharmacies and healthcare institutions. You are advised to check with the respective institutions for such information.