Medication Information Leaflet

​What is this medication for?

Alectinib is used to treat non-small cell lung cancer that has spread to other parts of the body. Your doctor will check for a gene mutation before starting you on this.

How should I take/use this medication?

  • Take Alectinib two times a day, after food. Take the exact dose that your doctor tells you to.
  • Do not break open or crush the capsule. Swallow the capsule whole.
    • Inform your doctor or pharmacist if you have difficulty swallowing.

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

If you forget to take a dose, skip the missed dose and take your next dose at the usual time. Do not take two doses at the same time to make up for the missed dose.

What precautions should I take?

Inform your healthcare professional if: 

  • You are allergic to this medication.
  • You or your partner becomes pregnant or is planning for pregnancy
    • You should use effective birth control during treatment and for at least 3 months after stopping Alectinib.
  • You are breastfeeding
    • Do not breastfeed during treatment and for 1 week after stopping Alectinib.
  • You have any other medical conditions such as having a slow heartbeat. 

What are some common side-effects of this medication?

  • Constipation
    • Drink more water or clear fluids (if you do not have a limit on the amount you can take each day).
    • Add more fibre to your diet by eating more fruits and vegetables.
  • Feeling tired and lack of energy
    • Do not drive or operate machinery when you feel tired.
  • Skin rash, sensitivity to sun
    • Avoid too much exposure to the sun. Use a sunscreen and lip balm that has a Sun Protection Factor (SPF) of 50 or more during treatment and for 7 days after the last dose of Alectinib.
  • Reduced red blood cell count

What are some rare but serious side-effects that I need to seek medical advice immediately?

  • Sudden onset of cough, chest pain, shortness of breath or fever
  • Dark urine or light coloured stools, nausea, vomiting, loss of appetite, stomach pain, yellowing of your eyes or skin
  • Very bad swelling of hands, feet or lower legs
  • Passing out very little urine although you are taking similar amount of water and fluid everyday
  • Slow heartbeat
  • Unusual giddiness or light-headedness
  • Very bad muscle soreness or weakness that does not go away 

The symptoms of a drug allergy include one or more of the following: 

  • Swollen face/eyes/lips/tongue
  • Difficulty in breathing
  • Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medication and see your healthcare professional immediately.

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

Inform your healthcare professional if you are taking or intend to take any other medication, supplements, traditional medications or herbal remedies. Some of them may affect how Alectinib works.

How should I store this medication?

Store in a cool and dry place, away from direct sunlight. Keep it in its original package. 

Keep this medication away from children. 

How should I throw away this medication safely?

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

You may refer to the following website if you need more information: 


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 (National Healthcare Group, 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.

Last updated on August 2022

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