What is Sotorasib used for?

non-small cell lung cancer with a KRAS G12C change; colorectal cancer with a KRAS G12C change, together with the antibody panitumumab.

What are the common side effects of Sotorasib?

Diarrhea. Nausea. Feeling tired. Muscle, bone, or joint pain. Cough. Changes in liver blood tests. Rash or dry skin, mostly when given with panitumumab.

When should I call my care team while taking Sotorasib?

Yellow skin or eyes, dark urine, or pain on the right side of your belly; New or worse cough, shortness of breath, or chest pain, which can be a sign of lung swelling; Diarrhea that does not get better with the medicine your team told you to use, or 4 or more extra stools a day; Feeling very weak or dizzy from not drinking or eating enough.

Sotorasib

Say it: soh-TOR-uh-sib · Brand names: Lumakras

Sotorasib is a targeted pill that blocks a growth signal in cancers with a KRAS G12C gene change.

What it is

Some cancers have a change in a gene called KRAS, known as G12C. This change keeps a growth switch turned on. Sotorasib locks the switch in the off position.

Often used for

non-small cell lung cancer with a KRAS G12C change
colorectal cancer with a KRAS G12C change, together with the antibody panitumumab

How you get it

It is a pill you take by mouth once a day, with or without food. People usually take it for as long as it works. Your schedule may be different.

Common side effects and what helps

Diarrhea. Drink plenty of fluids and ask your team which diarrhea medicine to keep at home.
Nausea. Eat small, bland meals.
Feeling tired. Rest when you need to and take short walks when you can.
Muscle, bone, or joint pain. Ask your team what pain medicine is safe for you.
Cough. Tell your team if it is new or getting worse.
Changes in liver blood tests. Your team will check these.
Rash or dry skin, mostly when given with panitumumab. Use moisturizer and sunscreen.

Call your care team right away if you have

Yellow skin or eyes, dark urine, or pain on the right side of your belly
New or worse cough, shortness of breath, or chest pain, which can be a sign of lung swelling
Diarrhea that does not get better with the medicine your team told you to use, or 4 or more extra stools a day
Feeling very weak or dizzy from not drinking or eating enough

Before you start, tell your team

If you take medicines for heartburn or stomach acid
If you have liver or lung problems
If you are pregnant, may become pregnant, or are breastfeeding
All the medicines, vitamins, and herbal products you take, since some can change how this medicine works

Good to know

Liver problems can happen. You will have liver blood tests often in the first few months.
Rarely, it causes serious lung swelling.
Stomach acid medicines can make it work less well. If you need an antacid, ask your team how to time it.

At home

Take it at about the same time each day.
If you cannot swallow the pills, ask your team. The label allows them to be mixed in plain water in a certain way.
If you miss a dose or throw up after a dose, ask your team what to do. Do not take an extra dose on your own.
Store the pills at room temperature in their original container, away from children and pets.
Wash your hands after touching the pills. Ask your team if others in your home should take special care.

Questions to ask

How long will I take this medicine?
What tests will I need, and how often?
Are any of my other medicines, foods, or supplements a problem with this medicine?
What should I do if I miss a dose?
Which side effects should I call you about right away, and which can wait?

Side effect guides

Sources

Quick answers

What is Sotorasib?: Sotorasib is a targeted pill that blocks a growth signal in cancers with a KRAS G12C gene change. Brand names: Lumakras.
What is Sotorasib used for?: non-small cell lung cancer with a KRAS G12C change; colorectal cancer with a KRAS G12C change, together with the antibody panitumumab.
How is Sotorasib given?: It is a pill you take by mouth once a day, with or without food. People usually take it for as long as it works. Your schedule may be different.
What are the common side effects of Sotorasib?: Diarrhea. Nausea. Feeling tired. Muscle, bone, or joint pain. Cough. Changes in liver blood tests. Rash or dry skin, mostly when given with panitumumab.
When should I call my care team while taking Sotorasib?: Yellow skin or eyes, dark urine, or pain on the right side of your belly; New or worse cough, shortness of breath, or chest pain, which can be a sign of lung swelling; Diarrhea that does not get better with the medicine your team told you to use, or 4 or more extra stools a day; Feeling very weak or dizzy from not drinking or eating enough.

Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.