WHY is this medicine prescribed?
Nelfinavir is used along with other medications to treat human immunodeficiency virus (HIV) infection. Nelfinavir is in a class of medications called protease inhibitors. It works by decreasing the amount of HIV in the blood. Although nelfinavir does not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses such as serious infections or cancer. Taking these medications along with practicing safer sex and making other lifestyle changes may decrease the risk of transmitting the HIV virus to other people.
HOW should this medicine be used?
Nelfinavir comes as a tablet and a powder to take by mouth. It is usually taken two to three times a day with food. Take nelfinavir at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take nelfinavir exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
If you are unable to swallow the tablet, you may put it in a glass and dissolve it in a small amount of water. Mix the liquid well, and drink it immediately. Rinse the glass with more water and swallow the entire mixture to make sure you have taken all of the medication.
Nelfinavir oral powder may be added to water, milk, formula, soy milk, or dietary supplements. Mix well, and drink all of the liquid right away in order to take the full dose. Your prescription label tells you how many scoops of nelfinavir powder to add to the liquid. If the mixture is not taken immediately it must be stored in the refrigerator and taken within 6 hours. Do not mix nelfinavir oral powder with acidic food or juice (orange juice, apple juice, or apple sauce). Do not mix nelfinavir with water in the original container.
Nelfinavir controls HIV infection but does not cure it. Continue to take nelfinavir even if you feel well. Do not stop taking nelfinavir without talking to your doctor. If you stop taking nelfinavir or skip doses, your infection may get worse or become resistant to medications.
Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.
Are there OTHER USES for this medication?
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.
What SPECIAL PRECAUTIONS should I follow?
Before taking nelfinavir,
What SPECIAL DIETARY instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do IF I FORGET to take a dose?
Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What SIDE EFFECTS can this medicine cause?
Nelfinavir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:
Nelfinavir contains a chemical found to cause cancer in laboratory animals. The Food and Drug Administration (FDA) has asked the manufacturer to make changes in the way nelfinavir is made to decrease the amount of this chemical in nelfinavir products. The risk to humans is unknown but may be higher in children and pregnant women. Talk to your doctor about the risks of taking nelfinavir.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What should I do in case of OVERDOSE?
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at http://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
What should I know about STORAGE and DISPOSAL of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). After nelfinavir powder has been added to liquid, the mixture may be kept at room temperature for up to 6 hours.
Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location - one that is up and away and out of their sight and reach. http://www.upandaway.org
Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website http://goo.gl/c4Rm4p for more information.
What OTHER INFORMATION should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your response to nelfinavir.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
Keep a supply of nelfinavir on hand. Do not wait until you run out of medication to refill your prescription.
Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.
This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.
The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.
AHFS® Patient Medication Information™ Copyright, 2025. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: January 15, 2022.