For Healthcare Providers

Side effects with ALECENSA® (alectinib)

What are the possible side effects of ALECENSA?

Learn about the side effects of ALECENSA so you can take note of any that you experience and discuss them with your care team.

Important Safety Information

Tell your doctor right away if you have any new or worsening symptoms such as those described below.

Possible serious side effect:

Liver icon

Liver problems (hepatotoxicity)

ALECENSA may cause liver injury. Your doctor will do blood tests at least every 2 weeks for the first 3 months, and then 1 time each month and as needed during treatment with ALECENSA.

Tell your doctor right away if you get any of the following signs and symptoms:

  • Feeling tired
  • Feeling less hungry than usual
  • Yellowing of your skin or the whites of your eyes
  • Dark urine
  • Itchy skin
  • Nausea or vomiting
  • Pain on the right side of your stomach area
  • Bleeding or bruising more easily than normal

Possible serious side effect:

Lungs icon

Lung problems

ALECENSA may cause severe or life-threatening swelling (inflammation) of the lungs during treatment. Symptoms may be similar to those symptoms from lung cancer.

Tell your doctor right away if you get any of the following signs and symptoms:

  • Trouble breathing 
  • Shortness of breath
  • Cough 
  • Fever

Possible serious side effect:

Kidneys icon

Kidney problems

ALECENSA may cause severe or life-threatening kidney problems.

Tell your doctor right away if you get any of the following signs and symptoms:

  • A change in the amount or color of your urine
  • New or worsening swelling in your legs or feet 

Possible serious side effect:

Heartbeat icon

Slow heartbeat (bradycardia)

ALECENSA may cause very slow heartbeats that can be severe. Your doctor will check your heart rate and blood pressure during treatment with ALECENSA. Tell your doctor if you take any heart or blood pressure medications. 

Tell your doctor right away if you get any of the following signs and symptoms:

  • Feeling dizzy 
  • Feeling lightheaded 
  • If you faint during treatment with ALECENSA

Possible serious side effect:

Arm pain icon

Muscle pain, tenderness, and weakness (myalgia)

Muscle problems are common with ALECENSA and can be severe. Your doctor will do blood tests at least every 2 weeks for the first month and as needed during treatment with ALECENSA.

Tell your doctor right away if you get any of the following signs and symptoms:

  • Unexplained muscle pain
  • Muscle pain that does not go away
  • Tenderness
  • Weakness

Possible serious side effect:

Red blood cells icon

Breakdown of healthy red blood cells earlier than normal (hemolytic anemia)

Hemolytic anemia can happen in some people who take ALECENSA. If this happens, you may not have enough healthy red blood cells. Your doctor may temporarily stop ALECENSA and do blood tests, if needed, to check for this problem. If you develop hemolytic anemia, your doctor may either restart you on ALECENSA at a lower dose when the hemolytic anemia goes away, or may stop your treatment with ALECENSA.

Tell your doctor right away if you get any of the following signs and symptoms:

  • Yellow skin (jaundice)
  • Weakness
  • Dizziness
  • Shortness of breath

The most common side effects of ALECENSA include:

  • constipation
  • tiredness
  • swelling in your hands, feet, ankles, face, and eyelids
  • rash
  • cough


These are not all of the possible side effects of ALECENSA. Tell your doctor if you have any side effect that bothers you or that does not go away. For more information, ask your doctor or pharmacist. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Genentech at (888) 835-2555.

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What should you tell your doctor before starting ALECENSA?

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These do not replace the advice of your healthcare team.

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Important Safety Information & Indications

Who is ALECENSA for?

ALECENSA is a prescription medicine used to treat adults with non-small cell lung cancer (NSCLC) that is caused by an abnormal anaplastic lymphoma kinase (ALK) gene:

  • To help prevent your lung cancer from coming back after your tumor has been removed by surgery (adjuvant), or 
  • As treatment if your lung cancer has spread to other parts of the body (metastatic)

Your doctor will perform a test to make sure that ALECENSA is right for you. It is not known if ALECENSA is safe and effective in children.

What is the most important information I should know about ALECENSA?

Everyone reacts differently to treatment with ALECENSA. It’s important to know the most serious and most common side effects with ALECENSA.

Your doctor may lower the dose or stop treatment with ALECENSA if any side effects occur. Contact your doctor right away if you have any of the following side effects.

ALECENSA may cause serious side effects, including:

Liver problems (hepatotoxicity). Liver problems are common with ALECENSA and can be severe. Your doctor will do blood tests at least every 2 weeks for the first 3 months, and then 1 time each month and as needed during treatment with ALECENSA to check your liver function. Tell your doctor right away if you get any of the following signs and symptoms:

  • Feeling tired
  • Feeling less hungry than usual
  • Yellowing of your skin or the whites of your eyes
  • Dark urine
  • Itchy skin
  • Nausea or vomiting
  • Pain on the right side of your stomach area
  • Bleeding or bruising more easily than normal 

Lung problems. ALECENSA may cause severe or life-threatening swelling (inflammation) of the lungs during treatment. Symptoms may be similar to those symptoms from lung cancer. Tell your doctor right away if you have any new or worsening symptoms, including trouble breathing, shortness of breath, cough, or fever.

Kidney problems. ALECENSA may cause severe kidney problems that can lead to death. Tell your doctor right away if you have a change in the amount or color of your urine, or if you get new or worsening swelling in your legs or feet.

Slow heartbeat (bradycardia). ALECENSA may cause very slow heartbeats that can be severe. Your doctor will check your heart rate and blood pressure during treatment with ALECENSA. Tell your doctor right away if you feel dizzy, lightheaded, or if you faint during treatment with ALECENSA. Tell your doctor if you take any heart or blood pressure medicines.

Severe muscle pain, tenderness, and weakness (myalgia). Muscle problems are common with ALECENSA and can be severe. Your doctor will do blood tests at least every 2 weeks for the first month and as needed during treatment with ALECENSA. Tell your doctor right away if you have any new or worsening signs and symptoms of muscle problems, including unexplained muscle pain or muscle pain that does not go away, tenderness, or weakness.

Breakdown of healthy red blood cells earlier than normal (hemolytic anemia). Hemolytic anemia can happen in some people who take ALECENSA. If this happens, you may not have enough healthy red blood cells. Your doctor may temporarily stop ALECENSA and do blood tests, if needed, to check for this problem. If you develop hemolytic anemia, your doctor may either restart you on ALECENSA at a lower dose when the hemolytic anemia goes away, or may stop your treatment with ALECENSA. Tell your doctor right away if you experience yellow skin (jaundice), weakness or dizziness, or shortness of breath.

What should I tell my doctor before taking ALECENSA?

Before you take ALECENSA, tell your doctor about all of your medical conditions, including if you:

  • Have liver problems
  • Have lung or breathing problems
  • Have a slow heartbeat
  • Are pregnant or plan to become pregnant. ALECENSA can harm your unborn baby.
    Females who are able to become pregnant:
    • Your doctor will do a test to see if you are pregnant before starting treatment with ALECENSA
    • You should use effective birth control (contraception) during treatment with ALECENSA and for 5 weeks after the last dose of ALECENSA
    • Tell your doctor right away if you become pregnant during treatment with ALECENSA or think you may be pregnant
    Males who have female partners that are able to become pregnant should use effective birth control (contraception) during treatment with ALECENSA and for 3 months after the last dose of ALECENSA
  • Are breastfeeding or plan to breastfeed. It is not known if ALECENSA passes into your breast milk. Do not breastfeed during treatment with ALECENSA and for 1 week after the last dose of ALECENSA. Talk to your doctor about the best way to feed your baby during this time

Tell your doctor about all the medicines you take, including prescription medicines, over-the-counter medicines, vitamins, and herbal supplements.

What should I avoid while taking ALECENSA?

Avoid spending time in the sunlight during treatment with ALECENSA and for 7 days after the final dose of ALECENSA. Your skin may be sensitive to the sun (photosensitivity) and you may burn more easily and get severe sunburns. Use sun protecting measures, such as sunscreen and lip balm with SPF 50 or greater to help protect against sunburn.

What are the possible side effects of ALECENSA?

The most common side effects of ALECENSA include:

  • constipation
  • tiredness
  • swelling in your hands, feet, ankles, face, and eyelids
  • rash
  • cough

These are not all of the possible side effects of ALECENSA. For more information, ask your doctor or pharmacist. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Genentech at (888) 835-2555.

Please see additional Important Safety Information in full Prescribing Information, including Patient Information.