Viracept (nelfinavir) is a protease inhibitor (PI) used to treat human immunodeficiency virus (HIV) in people ages 2 years and older. It works by preventing the HIV virus from making copies of itself and spreading. You take Viracept (nelfinavir) by mouth, typically twice or three times a day with a meal. One of the most common side effects Viracept (nelfinavir) can cause is diarrhea. Your provider might recommend over-the-counter medications, like loperamide (Imodium A-D), to help ease your symptoms.
Treatment of HIV
Viracept (nelfinavir) is a protease inhibitor. It works by blocking a protein called protease that helps the HIV virus infect your cells. When protease is blocked by Viracept (nelfinavir), the HIV virus can't make copies of itself and infect healthy cells.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Less common
bleeding gums
blood in the urine or stools
bloody, black, tarry stools
blurred vision
chills
coma
confusion
cool, pale skin
darkened urine
dehydration
dizziness
fast heartbeat
flushed, dry skin
fruity mouth odor
increased hunger
increased thirst
increased urination
indigestion
joint pain, stiffness, or swelling
loss of appetite
nervousness
nightmares
painful or difficult urination
pains in the stomach, side, or abdomen, possibly radiating to the back
pinpoint red spots on the skin
seizures
shakiness
slurred speech
sores, ulcers, or white spots on the lips or in the mouth
sweating
swelling of the feet or lower legs
swollen glands
trouble breathing
unusual bleeding or bruising
unusual tiredness or weakness
vomiting
vomiting of blood or material that looks like coffee grounds
yellow eyes or skin
Incidence not known
Clay-colored stools
difficulty with breathing
drowsiness
fainting
headache
irregular heartbeat
muscle tremors
noisy breathing
rapid, deep breathing
recurrent fainting
restlessness
skin rash
unpleasant breath odor
vomiting of blood
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Less common
Acid or sour stomach
belching
burning, crawling, itching, numbness, prickling, "pins and needles" , or tingling feelings
difficulty in moving
discouragement
feeling sad or empty
increase in body movements
irritability
loss of interest or pleasure
muscle aches, cramps, pain, or stiffness
muscular tenderness, wasting or weakness
passing gas
redistribution or accumulation of body fat
sleepiness or unusual drowsiness
trouble concentrating
trouble sleeping
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Tablets can be dissolved in water
Can be used in children as young as 2 years old
Not a whole lot of side effects
Taken multiple times a day
One day's dose can be as many as 10 tablets
A lot of medication interactions, including some other HIV ARVs
Consider using a weekly pill box or smartphone app to help you remember to take Viracept (nelfinavir) and other HIV medications. Each dose of Viracept (nelfinavir) is made up of multiple tablets and you need to take a dose 2 to 3 times a day, which can be hard to keep track of.
Always take Viracept (nelfinavir) with food. This will help with how your body absorbs the medication. Tell your healthcare provider if you're concerned about consistent, reliable access to food. There might be resources they can help you with, or they might choose to have you on a medication that doesn't need to be taken with food.
If you have a hard time swallowing the Viracept (nelfinavir) tablets, try making a mixture to drink. Put the tablet in a small amount of water. Once it dissolves, mix the liquid until it's cloudy, then drink the mixture right away. Rinse the glass with water and drink the rinse so that you make sure you're getting the whole dose.
If you're taking the oral powder version of Viracept (nelfinavir), you can mix it with water, milk, formula, soy milk or dietary supplements. If you don't take your full dose right away, it can be stored in the refrigerator for up to 6 hours. After this amount of time, you must throw the mixture away.
Talk to your healthcare provider or pharmacist before starting any new medications. Viracept (nelfinavir) interacts with a lot of medications, and can make the levels in your body too high and cause more side effects. Also make sure to tell your providers if you stop taking Viracept (nelfinavir). Your providers might need to lower the dose of other medications to adjust for the interaction.
If you take hormonal birth control pills, you should also use another form of contraception. The birth control pills might not work as well while you're taking Viracept (nelfinavir).
Viracept (nelfinavir) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Taking other medications or supplements
Viracept (nelfinavir) can interact with many other medications. Depending on what other medications you're taking, your provider might need to adjust the dose of Viracept (nelfinavir) or those other medications. Otherwise, the interactions can either cause the levels of Viracept (nelfinavir) to drop too low and not work well to fight HIV; or the levels of Viracept (nelfinavir) might be too high and cause more unwanted side effects. Talk to your healthcare provider or pharmacist before starting or stopping any medication.
Risk factors: Use of protease inhibitors
Viracept (nelfinavir) and other protease inhibitors can raise your blood sugar levels and lead to diabetes. If you already have diabetes, it can make it worse. Be sure to keep your regularly scheduled appointments and check your blood sugar at home if your provider tells you to.
Risk factors: Taking HIV ARVs
Some people taking HIV ARVs, including Viracept (nelfinavir), have noticed changes to the way fat is located in the body. This might cause more fat in the abdomen and upper back, and less fat in the face, arms, and legs. Scientists and health care providers don't really know why this happens.
Risk factors: Weakened immune system | Current untreated infection
Taking Viracept (nelfinavir) and other HIV medications can raise your risk of immune reconstitution inflammatory syndrome (IRIS). This can happen after your immune system starts to recover with the help of HIV treatment. Once your immune system is strong enough to fight off infections, this can result in a lot of inflammation. Too much inflammation can lead to symptoms of IRIS. Call your provider if you experience fever, difficulty breathing, or sudden changes to your health after starting Viracept (nelfinavir).
If you have moderate or severe liver problems, let your provider know. You likely won't be able to take Viracept (nelfinavir) and they'll talk with you about other options.
Viracept (nelfinavir) contains phenylalanine, a component of the artificial sweetener aspartame. If you have a genetic condition called phenylketonuria (PKU), taking this medication can be dangerous for you. Let your provider know if you have PKU so they can prescribe a different formulation of Viracept (nelfinavir) that might be safer for you.
Viracept (nelfinavir) is available as 250 mg tablets and 625 mg tablets that can be swallowed or dissolved in a small amount of water. For people or children who can't swallow the tables, there's also an oral powder version that can be mixed with milk, formula, soy formula, soy milk, or dietary supplements.
Adults and adolescents (ages 13 years and older): The typical dose is 1,250 mg by mouth twice a day with meals, or 750 mg by mouth three times a day with meals.
Children (ages 2 to 12 years old): Your child's provider will calculate the dose based on the child's weight. The typical dose ranges from 45 mg/kg to 55 mg/kg by mouth twice a day with meals, or 25 mg/kg to 35 mg/kg three times a day with meals.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Taking Viracept (nelfinavir) with certain medications that are highly dependent on CYP3A metabolism (break down)
Treatment of HIV infection in people aged 3 years and older
Treatment of HIV infection (used with other antiretroviral medications)
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AGOURON. (2023). Viracept- nelfinavir mesylate tablet, film coated [package insert]. DailyMed.
Clinical Info HIV.gov. (n.d.). Immune reconstitution inflammatory syndrome (IRIS).
Clinical Info HIV.gov. (n.d.). Protease inhibitor (PI).
Maenza, J., et al. (1998). Combination antiretroviral therapy for HIV infection. American Family Physician.
National Human Genome Research Institute. (2014). About phenylketonuria.
State of Florida DOH Central Pharmacy. (2010). Viracept - nelfinavir mesylate tablet, film coated [package insert]. DailyMed.
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