This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
Brand Names: US
Hernexeos
What is this drug used for?
- It is used to treat lung cancer.
What do I need to tell my doctor BEFORE I take this drug?
- If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you are breast-feeding. Do not breast-feed while you take this drug and for 2 weeks after your last dose.
This drug may interact with other drugs or health problems.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take this drug?
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- Have your blood work and heart function checked as you have been told by your doctor.
- High cholesterol and triglyceride levels have happened with the oral form of this drug. If you have high cholesterol or triglycerides, talk with your doctor.
- This drug may affect fertility. Fertility problems may lead to not being able to get pregnant or father a child. If you plan to get pregnant or father a child, talk with your doctor before taking this drug.
- This drug may cause harm to an unborn baby. A pregnancy test may be done before you start this drug to show that you are NOT pregnant.
- If you may become pregnant, use birth control while taking this drug and for 2 weeks after your last dose. If you become pregnant, call the doctor right away.
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of electrolyte problems like mood changes; confusion; muscle pain, cramps, or spasms; weakness; shakiness; change in balance; an abnormal heartbeat; seizures; loss of appetite; or severe upset stomach or throwing up.
- Fever, chills, or sore throat; any unexplained bruising or bleeding; or feeling very tired or weak.
- Lung problems have happened with this drug. These problems can be severe or life-threatening. Signs of lung problems may be like signs of lung cancer. Call your doctor right away if you have any new or worse signs of lung or breathing problems like shortness of breath or other trouble breathing, chest pain, cough with or without mucus, or fever.
- Liver problems have happened with this drug. Sometimes, these have been life-threatening. Call your doctor right away if you have signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- Some heart problems have happened with this drug. Call your doctor right away if you have a cough, dizziness or passing out, tiredness, shortness of breath, a big weight gain, or swelling in the arms or legs. Call your doctor right away if you feel like your heart is beating fast or pounding.
What are some other side effects of this drug?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Upset stomach or throwing up.
- Feeling tired or weak.
- Change in nails.
- Muscle or joint pain.
- Signs of a common cold.
- Mouth irritation or mouth sores.
- Headache.
- Diarrhea is common with this drug. Sometimes diarrhea can be severe and may cause dehydration. Talk with your doctor about what to do to help with diarrhea and prevent dehydration. Call your doctor right away if you have diarrhea that does not go away or is severe.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.
You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
How is this drug best taken?
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take with or without food.
- Swallow whole with water. Do not chew, break, or crush.
- Keep taking this drug as you have been told by your doctor or other health care provider, even if you feel well.
- If you throw up after taking a dose, do not repeat the dose. Take your next dose at your normal time.
What do I do if I miss a dose?
- Take a missed dose as soon as you think about it.
- If it has been more than 12 hours since the missed dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
How do I store and/or throw out this drug?
- Store tablets in the original container at room temperature. Keep the cap tightly closed.
- Store in a dry place. Do not store in a bathroom.
- The bottle has a desiccant in it to keep the drug dry. Keep the desiccant in the bottle. Do not eat or swallow the desiccant.
- After opening, throw away any part not used after 3 months.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
General drug facts
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else’s drugs.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
Consumer Information Use and Disclaimer
This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.
Last Reviewed Date
2026-03-19
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