Adagrasib: what it treats, how to take it, and side effects
Last updated September 7, 2026.
**Adagrasib is a targeted oral cancer medicine, a KRAS G12C inhibitor, sold under the brand name Krazati.** It locks a mutated form of the KRAS protein, called G12C, into an off position so that the signal telling those cancer cells to grow and divide is switched off. Because only tumors carrying that specific mutation respond, your care team confirms the KRAS G12C mutation with a tumor or blood test before you start. The most important safety point is that adagrasib can cause severe diarrhea, liver injury, lung inflammation and heart rhythm changes, so scheduled blood tests and prompt reporting of new symptoms are part of taking it.
What does it treat?
Adagrasib treats adults with non-small cell lung cancer that is locally advanced or metastatic and carries a KRAS G12C mutation, after at least one prior systemic treatment such as chemotherapy or immunotherapy. It is also approved, in combination with cetuximab, for adults with locally advanced or metastatic colorectal cancer with a KRAS G12C mutation who have already received fluoropyrimidine, oxaliplatin and irinotecan based chemotherapy. It is not a cure and it is not used for cancers without the G12C mutation, so the tumor test result drives the whole decision. In practice people are started on it when scans show growth on a previous regimen, or when they cannot tolerate more chemotherapy, and the goal is to shrink or hold the tumor and ease symptoms such as cough, breathlessness or bowel changes. There are no combination pills that contain adagrasib; when it is paired with cetuximab, the cetuximab is a separate infusion given by your oncology team.
How do you take it?
Adagrasib comes as 200 mg tablets. The usual adult dose is 600 mg (three tablets) by mouth twice a day, about 12 hours apart, which is a ceiling of 1,200 mg in 24 hours. Swallow the tablets whole with water and do not chew, crush or split them. You can take them with or without food. If your oncologist needs to lower the dose for side effects, the steps are 400 mg twice daily, then 600 mg once daily; if you cannot tolerate 600 mg once daily, the drug is stopped. If you miss a dose by more than 4 hours, skip it and take your next dose at the usual time, and never double up. If you vomit after a dose, do not repeat it; wait for the next scheduled dose. Acid reducers matter: avoid proton pump inhibitors such as omeprazole and H2 blockers such as famotidine while on adagrasib, because they lower how much drug you absorb. If you need something for reflux, a local antacid can be taken 4 hours before or 10 hours after your adagrasib dose. Do not stop or pause adagrasib on your own; call your oncology team the same day if you have watery stools that keep you from drinking, yellowing of the skin or eyes, dark urine, new or worsening cough or shortness of breath, fever, or fainting and palpitations.
Side effects to know
- Common: Most people notice at least some diarrhea, nausea, vomiting, tiredness, muscle or joint aches, swelling in the legs, reduced appetite, constipation or belly pain, and blood tests often show changes in liver enzymes, kidney values, salts such as sodium and magnesium, and blood counts.
- Serious: Stop and get medical help right away for severe or bloody diarrhea with dizziness or inability to keep fluids down, yellowing of the eyes or skin with dark urine or right upper belly pain, or new or worsening cough, shortness of breath or fever, which can signal inflammation of the lungs. Fainting, a racing or pounding heartbeat, or a seizure can mean a dangerous heart rhythm from QT prolongation and needs emergency care.
Who should not take it?
Adagrasib is not for cancers without a confirmed KRAS G12C mutation, and safety in children has not been established. Tell your doctor first if you have liver disease, kidney disease, existing lung scarring or interstitial lung disease, a long QT interval or other heart rhythm problem, a slow heart rate, heart failure, or low potassium or magnesium. Drug interactions are a major issue: avoid strong CYP3A4 inducers such as rifampin, carbamazepine, phenytoin and St. John's wort, which can make adagrasib stop working; discuss strong CYP3A inhibitors such as ketoconazole, itraconazole, clarithromycin, ritonavir and grapefruit juice, which raise drug levels; and avoid proton pump inhibitors and H2 blockers. Adagrasib itself raises levels of many other medicines, including some statins, midazolam, digoxin, warfarin and certain sedatives and pain medicines, so bring your full list including over the counter products and supplements to every visit. Also flag any other medicine that prolongs the QT interval, such as ondansetron, methadone, azithromycin, amiodarone, sotalol or citalopram. Adagrasib can harm an unborn baby based on animal findings and how it works, so it is not used in pregnancy; if you can become pregnant, use effective birth control during treatment and for 1 week after the last dose, and confirm you are not pregnant before starting. Do not breastfeed during treatment and for 1 week after the final dose. There is no fixed alcohol rule on the label, but because adagrasib can inflame the liver and worsen nausea and dehydration, keep alcohol to a minimum or avoid it, and skip it entirely if your liver enzymes are up.
When is it an emergency?
Call 911 in the US for collapse, fainting, a seizure, chest pain, a fast or irregular heartbeat that will not settle, sudden trouble breathing, or swelling of the lips, tongue or throat with hives. For a suspected overdose, or if someone takes extra tablets or a child swallows any, call Poison Control at 1-800-222-1222 right away, even if the person seems fine; there is no specific antidote, and the main worries are severe vomiting and diarrhea with dehydration and a dangerous heart rhythm. Get same day medical care, not next week, for more than about six watery stools a day, diarrhea you cannot control with the medicine your team gave you, vomiting that stops you from drinking, very little urine, yellow eyes or skin, dark urine, a fever over 100.4 F, or new cough and breathlessness.
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Common questions
What is the maximum dose of adagrasib in a day?
The standard adult dose is 600 mg twice a day, which is 1,200 mg in 24 hours, and that is the ceiling. Each tablet is 200 mg, so a full dose is three tablets in the morning and three about 12 hours later. If side effects come up, your oncologist steps the dose down to 400 mg twice daily, then to 600 mg once daily, rather than raising it. There is no situation where you take more than 600 mg at one time. If you miss a dose by more than 4 hours, skip it and take the next one on schedule instead of doubling up.
Can I drink alcohol while taking adagrasib?
The label does not list a direct alcohol interaction, but alcohol and adagrasib both stress the liver, and adagrasib already raises liver enzymes in a meaningful share of people. Alcohol also worsens nausea, dehydration and the diarrhea this drug commonly causes. The practical advice is to keep it to a minimum or skip it, especially in the first several weeks while your liver blood tests are being checked. If your ALT or AST come back elevated, avoid alcohol completely until your team says otherwise. Ask your oncologist about your own labs before deciding.
Is adagrasib safe during pregnancy or breastfeeding?
No. Based on how adagrasib works and on animal studies, it can harm an unborn baby, so it is not used in pregnancy. If you can become pregnant, your team will confirm you are not pregnant before you start, and you should use effective birth control during treatment and for 1 week after your last dose. Do not breastfeed while taking adagrasib or for 1 week after the final dose. Tell your oncologist right away if you become pregnant or think you might be.
Do I take adagrasib with food, and what about heartburn medicines?
You can take adagrasib with or without food, so pick whichever timing you will remember twice a day, roughly 12 hours apart. Swallow the tablets whole with water; do not crush, chew or split them. Acid reducers are the real issue, because adagrasib dissolves poorly when stomach acid is suppressed. Avoid proton pump inhibitors such as omeprazole, esomeprazole and pantoprazole, and avoid H2 blockers such as famotidine. If you need reflux relief, ask about a local antacid and take it 4 hours before or 10 hours after your adagrasib dose.
What are the signs of taking too much adagrasib?
Overdose mainly shows up as intense nausea, repeated vomiting and heavy watery diarrhea leading to dehydration, plus dizziness, weakness, palpitations, fainting or an irregular heartbeat from QT prolongation. There is no specific antidote, so care is supportive with fluids, salt replacement and heart monitoring. Call Poison Control at 1-800-222-1222 right away if extra tablets were taken or a child got into them, even if the person feels well. Call 911 for fainting, a seizure, chest pain or trouble breathing. Bring the bottle so the team knows the exact strength and count.
Which medicines interact with adagrasib?
Strong CYP3A4 inducers such as rifampin, carbamazepine, phenytoin and St. John's wort can drop adagrasib levels enough to make it stop working, so they are avoided. Strong CYP3A inhibitors such as ketoconazole, itraconazole, clarithromycin and ritonavir, along with grapefruit juice, push levels up and need your oncologist's input. Adagrasib also raises blood levels of many other drugs, including some statins, midazolam, digoxin and warfarin, which may need dose changes or monitoring. Anything that prolongs the QT interval, such as ondansetron, methadone, azithromycin, amiodarone, sotalol or citalopram, adds to the heart rhythm risk. Give your full medicine and supplement list to your oncology pharmacist before starting and any time something new is added.