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Efavirenz Coupon - Efavirenz 600mg tablet

efavirenz

Generic Sustiva
Used for HIV Treatment
Used for HIV Treatment

Efavirenz (Sustiva) is a medication that's used in combination with other antiretroviral (ARV) therapy to treat human immunodeficiency virus (HIV) infections. It comes as oral tablets and capsules that are swallowed whole. The capsules can also be opened up and sprinkled in liquid for people who have trouble swallowing. Some side effects of this medication are rash, diarrhea, and nausea. Efavirenz (Sustiva) is available as both a brand-name and generic medication.

Last reviewed on June 14, 2023
basics-icon

What is Efavirenz (Sustiva)?

What is Efavirenz (Sustiva) used for?

  • Treatment of HIV infection in people ages 3 months and older

How Efavirenz (Sustiva) works

Efavirenz (Sustiva) is a non-nucleoside reverse transcriptase inhibitor (NNRTI). It blocks an enzyme found in HIV called reverse transcriptase that usually helps the virus make copies of itself. By blocking reverse transcriptase, efavirenz (Sustiva) prevents the HIV virus from doing so and from spreading.

Drug Facts

Common BrandsSustiva (brand no longer available)
Drug ClassHIV ARV
Controlled Substance ClassificationNot a controlled medication
Generic StatusLower-cost generic available
AvailabilityPrescription only
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What are the side effects of Efavirenz (Sustiva)?

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

The following side effects were reported in adults taking this medication with other HIV ARVs. Side effects might differ in children.
  • Rash (5-16%)
  • Diarrhea (3-14%)
  • Pain (1-13%)
  • Higher triglyceride (fat) levels (6-11%)
  • Low white blood cell count (2-10%)
  • Nausea (2-10%)
  • Dizziness (2-9%)
  • Feeling tired (2-8%)
  • Higher liver enzymes (5-8%)
  • Headache (2-8%)
  • Difficulty sleeping (7%)
  • Vomiting (3-6%)
  • Trouble concentrating (3-5%)

Other Side Effects

  • Abnormal dreams
  • Indigestion
  • Belly pain
  • Feeling nervous
  • Weight loss
  • Feeling weak
  • Itching

Serious Side Effects

Contact your healthcare provider immediately if you experience any of the following.
  • Severe allergic reactions and skin reactions: fever, rash, general discomfort, muscle or joint pain, mouth sores, blisters, facial swelling
  • Liver problems: nausea, vomiting, not feeling hungry, pain in the right side of the stomach, yellowing of the whites of the eyes or skin, dark-colored urine, light-colored stool
  • Abnormal heart rhythm: chest pounding, trouble breathing, chest pain, feeling faint or lightheaded
  • Mood problems: anxiety, confusion, agitated, restlessness, depressed, hallucination(s)
  • Thoughts of self-harm

Source: DailyMed

The following side effects have also been reported

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:

More common

Depression

skin rash or itching

Less common

Blood in the urine

difficult or painful urination

pain in the lower back or side

Rare

Abdominal or stomach pain

blistering

changes in vision

clumsiness or unsteadiness

confusion

convulsions (seizures)

cough

dark urine

delusions

double vision

fainting

fast or pounding heartbeat

fever or chills

headache (severe and throbbing)

hives

inappropriate behavior

loss of appetite

mood or mental changes (severe)

muscle cramps or pain

nausea or vomiting

nerve pain

open sores

pain, tenderness, bluish color, or swelling of the leg or foot

rapid weight gain

seeing, hearing, or feeling things that are not there

sense of constant movement of self or surroundings

sores, ulcers, or white spots in the mouth or on the lips

speech disorder

swelling or tenderness in the upper abdominal or stomach area

swelling of the hands, arms, feet, or legs

thoughts of suicide or attempts at suicide

tightness in the chest

tingling, burning, numbness, or pain in the hands, arms, feet, or legs

tingling, burning, or prickling sensations

tremor

troubled breathing

unusual tiredness

weight loss

yellow eyes or skin

Incidence not known

Actions that are out of control

attack, assault, or force

continuing vomiting

decreased awareness or responsiveness

delusions of persecution, mistrust, suspiciousness, or combativeness

difficult or labored breathing

early appearance of redness or swelling of the skin

general feeling of tiredness or weakness

irregular heartbeat recurrent

irritability

late appearance of rash with or without weeping blisters that become crusted, especially in sun-exposed areas of the skin, may extend to unexposed areas

light-colored stools

mimicry of speech or movements

mutism

negativism

nervousness

peculiar postures or movements, mannerisms, or grimacing

severe sleepiness

talking, feeling, and acting with excitement

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

Diarrhea

dizziness

drowsiness

headache

increased sweating

poor concentration

trouble sleeping

Less common or rare

Abnormally decreased sensitivity, particularly to touch

agitation or anxiety

belching

change in sense of taste or smell

dry mouth

excessive gas

false sense of well-being

flaking and falling off of the skin

flushing

general feeling of discomfort

heartburn

indigestion

joint pain

lack of feeling or emotion

loss of hair

loss of memory

loss of sense of reality

mood changes

pain

painful, red, hot, or irritated hair follicles

ringing in the ears

stomach discomfort

unusual dreams

weakness

Incidence not known

Difficulty having a bowel movement (stool)

discoloration of the fingernails or toenails

dizziness or lightheadedness

feeling of constant movement of self or surroundings

increased amount of fat in the upper back and neck, or around the chest and stomach area

lose fat from the legs, arms, and face

sensation of spinning

swelling of the breasts or breast soreness in both females and males

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.

pros-and-cons

Pros and cons of Efavirenz (Sustiva)

thumbs-up

Pros

Only taken once a day

Capsule form can be opened and sprinkled on soft food or liquid, such as applesauce or milk, so convenient for people with difficulty swallowing pills

Available as a lower-cost generic medication

Can be used in young children 3 months and older who weigh over 7.7 lbs

thumbs-down

Cons

Has many potentially serious side effects and risks (e.g., nerve issues, irregular heartbeat)

Needs to be taken on an empty stomach

Not recommended during pregnancy

Interacts with a lot of medications

pharmacist-tips

Pharmacist tips for Efavirenz (Sustiva)

pharmacist
  • If you have trouble swallowing, open efavirenz (Sustiva) oral capsules and mix the content with 1-2 teaspoons of soft food (apple sauce) or liquid (infant formula, water). Take the entire mixture within 30 minutes of mixing. Finally, add small amounts of food or liquid to any leftovers, stir, and take again to make sure you got all the medication. Avoid eating for 2 hours after taking a dose of efavirenz (Sustiva).

    • Take efavirenz (Sustiva) on an empty stomach at bedtime to lower the risk of certain side effects from this medication.

      • If your child is taking efavirenz (Sustiva), tell their provider if your child experiences any changes in weight. Your child's dose is based on their weight, so the dose might need to be changed depending on how much the change in weight is.

        • Make sure to get your routine blood tests done on time while you’re taking efavirenz (Sustiva). This helps your provider make sure the medication is working for you and not causing side effects.

          • Tell your provider immediately if you experience symptoms of seizure, depression, or changes in mood while taking efavirenz (Sustiva).

            • Efavirenz (Sustiva) can cause you to feel dizzy and lightheaded. Avoid driving or do activities that require a lot of focus until you know how this medication affects you.

              • Let your provider or pharmacist know what medications you're taking or planning to take, including over-the-counter products and supplements. Efavirenz (Sustiva) can interact with many medications. These interactions can affect how well your medications work or how safe they are for you.

                • Talk to your provider before stopping efavirenz (Sustiva) or any of your HIV medications. Doing so can cause the virus to spread and become harder to treat.

                  faqs

                  Frequently asked questions about Efavirenz (Sustiva)

                  How long does efavirenz (Sustiva) side effects last?
                  How long the side effects of efavirenz (Sustiva) last can differ depending on which side effects you're experiencing. For example, people who took efavirenz (Sustiva) reported side effects like dizziness, trouble sleeping, and difficulty concentrating within 1-2 days of starting this medication. But many people experienced these side effects easing or going away after 2 to 4 weeks of treatment. Another example is that in general, people who took efavirenz (Sustiva) in clinical studies noticed a rash within the first 2 weeks of starting treatment. But for most people, the rash disappeared within a month. Keep in mind that not all side effects will go away on their own and sometimes you need more medical attention (such as with seizures or liver problems). If you've more questions about a particular side effect of efavirenz (Sustiva), talk with your provider.
                  Why is efavirenz (Sustiva) taken on an empty stomach?
                  In clinical studies, people taking efavirenz (Sustiva) with food absorbed more of the medication in their body. This leads to more side effects, such as diarrhea and vomiting. As a result, taking efavirenz (Sustiva) on an empty stomach can help lower the risk of these side effects.
                  Why is efavirenz (Sustiva) taken at night?
                  Efavirenz (Sustiva) can typically cause nerve problems, such as dizziness, trouble concentrating, drowsiness, unusual dreams, and not able to balance. Taking this medication at bedtime can help you better tolerate these side effects.
                  Can efavirenz (Sustiva) be used as PEP?
                  Efavirenz (Sustiva) is typically not the first-choice for PEP, also known as post-exposure prophylaxis (prevention). PEP is a combination of HIV medications for people who might've been exposed to HIV during sex, through sharing needles, or other way. According to the CDC guidelines, efavirenz (Sustiva) is only used in PEP regimen if an expert in HIV infection has been consulted. Remember that PEP regimen needs to be taken within 3 days of exposure to greatly lower the risk of HIV infection. Talk to your provider about the best PEP option for you.
                  Can efavirenz (Sustiva) be used in pregnancy?
                  No, you shouldn't take efavirenz (Sustiva) during pregnancy and for at least 3 months after your last dose. Efavirenz (Sustiva) can raise the risk for neural tube defects in babies when it's taken during the first trimester of pregnancy. If you're able to become pregnant, your provider will ask to use 2 forms of effective birth control while you're taking efavirenz (Sustiva). Keep in mind that certain hormonal birth controls won't work as well if you're taking efavirenz (Sustiva). If you're pregnant or thinking of becoming pregnant, let your provider know right away. They can talk with you about safer options for treating HIV during pregnancy.
                  Will efavirenz (Sustiva) affect how well my birth control pills work?
                  Based on how efavirenz (Sustiva) works, it might cause birth controls with progestins to not work as well. This can raise your chance of becoming pregnant. Talk with your provider if you're concerned about getting pregnant during treatment. Always use a condom as an additional form of birth control. Aside from preventing pregnancy, most condoms work well in preventing HIV transmission.
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                  warings-icon

                  What are the risks and warnings for Efavirenz (Sustiva)?

                  Efavirenz (Sustiva) 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-warning

                  Heart rhythm problems (QT prolongation)

                  • Risk factors: History of heart problems, slow heart rate, or other abnormal heart rhythms (arrhythmias) | Personal or family history of long QT syndrome | Taking other medications that cause QT prolongation

                    Efavirenz (Sustiva) can affect your heart rhythm, which can be serious and life-threatening. One example includes lengthening the time it takes for your heart to pump and then relax. This is known as QT prolongation. Your risk for QT prolongation is higher if you have certain factors, including heart rhythm problems or are taking other medications that cause heart rhythm problems, such as amiodarone (Pacerone), among others. If you feel your chest pounding, have trouble breathing or chest pain, or feel faint or lightheaded while taking efavirenz (Sustiva), call 911 right away.

                    risk-warning

                    Effects on the brain, nerves, and mental health

                    • Risk factors: History of seizures, nerve damage, or mental health | Medical conditions that raise the risk of seizures | Taking mental health medications or medications that raise the risk of seizures | Injection drug use

                      Though rare, efavirenz (Sustiva) can raise your risk of seizures, dizziness, abnormal dreams, hallucinations, and trouble sleeping. For people who do experience these side effects, symptoms are likely to happen in the first 1-2 days of treatment and usually go away after 2-4 weeks.

                      Efavirenz (Sustiva) can also put you at risk for nerve damage that can affect your balance or cause confusion. These nerve problems can occur month to years after starting treatment. Talk to your provider right away if you experience dizziness, trouble concentrating, or drowsiness after starting this medication.

                      In addition, efavirenz (Sustiva) can also raise your risk of depression, suicidal thoughts or behavior, aggressive behavior, psychosis, and nervousness. These changes in behavior or thoughts are more likely to happen if you have a history of mental health or are taking medications for mental health. If you experience any of these side effects, seek medical help right away or contact your provider. They can help manage your treatment.

                      risk-warning

                      Harm to unborn baby

                      Taking efavirenz (Sustiva) during early pregnancy might raise the risk for birth defects called neural tube defects in babies. Because of this potential risk, you're recommended to avoid getting pregnant during treatment and for 3 months after the last dose.

                      If you're able to have a child, your provider will ask you to take a pregnancy test to check if it's safe for you to take efavirenz (Sustiva). You'll need to use 2 forms of effective birth controls during your treatment with efavirenz (Sustiva). Keep in mind that efavirenz (Sustiva) can cause hormonal birth controls to not work as well. If you're pregnant or are planning to become pregnant, discuss your HIV treatment options with your provider.

                      risk-warning

                      Severe skin and allergic reactions

                      Efavirenz (Sustiva) can sometimes cause rash and other severe skin reactions. These reactions typically appear in the first 2 weeks of treatment and usually resolve within a month. If you have a mild or moderate rash, continue to take efavirenz (Sustiva) and let your provider know. If you have a severe rash or your rash gets worse, talk with your provider right away. In rare cases, if you experience a severe rash with fever, general discomfort, muscle or joint pain, mouth sores, blisters, or facial swelling, stop taking efavirenz (Sustiva) right away and get medical attention.

                      risk-warning

                      Liver problems

                      • Risk factors: Hepatitis B or C | History of liver problems

                        Efavirenz (Sustiva) can cause life-threatening liver problems. Your provider will order blood tests for you before and during treatment so they can make sure this medication is safe for your liver. Let your provider know immediately if you experience signs and symptoms of liver damage, such as feeling sleepy, nausea, loss of appetite, light-colored stool, upper right stomach pain, yellowing of the skin or eyes, or dark urine.

                        risk-warning

                        Higher cholesterol levels

                        Efavirenz (Sustiva) raises the amount of cholesterol and triglycerides (fats) in your blood, which can put you at higher risk for a heart attack or stroke. Your provider will monitor your blood works before and during treatment with this medication to make sure it's safe for you. If your cholesterol levels are too high, your might need to take medications to help keep them under control. Keep in mind that certain cholesterol medications, such as atorvastatin, pravastatin, and simvastatin (Zocor), might not work as well when taken with efavirenz (Sustiva). Make sure to let your provider know all the medications you're taking before being prescribed new ones.

                        risk-warning

                        Changes in body fat

                        Rarely, people taking HIV medications, such as efavirenz (Sustiva), have experienced changes in body fat. These changes include fat buildup in the back of the neck, breast, and around the middle of the body. Some people also lost fat from the legs, arms, and face. It's not clear whether efavirenz (Sustiva) causes these changes to body fat, why this happens, and whether it will affect your health in the future. Let your provider know if these changes occur while you're taking efavirenz (Sustiva).

                        risk-warning

                        Overactive immune system

                        Taking combination ARV therapy, such as efavirenz (Sustiva) with other HIV medications, can cause changes to your immune system called immune reconstitution syndrome. This condition happens when your immune system becomes overly active after you start combination therapy. So your immune system begins to fight off different infections that it was too weak to fight off before you started treatment. In rare cases, your immune response might improve too much with treatment that it starts to attack normal cells in your body (autoimmune). You can develop these conditions as early as during the first few weeks of treatment or many months later. Tell your healthcare provider right away if you start having any new symptoms, such as fever, pain, hair loss, bulging eyes, or sweating, after starting efavirenz (Sustiva).

                        risk-warning

                        Interactions with other medications

                        Some medications can interfere with how well your body gets rid of efavirenz (Sustiva) from your system. This can affect the amount of efavirenz (Sustiva) in your body, how well it works, and the risk of side effects.

                        Taking certain anti-seizure medications (e.g., carbamazepine (Tegretol)) or tuberculosis medication (e.g., rifampin (Rifadin)) can lower the amount of efavirenz (Sustiva) in your body. This can make efavirenz (Sustiva) not work as well to treat your HIV. So this combination must be avoided.

                        Efavirenz (Sustiva) also interferes with how your body gets rid of other medications. For example, taking efavirenz (Sustiva) with medications like diltiazem (Cardizem) can lower the amount of diltiazem in your body. This can cause your blood pressure to not be controlled. In addition, taking efavirenz (Sustiva) with warfarin (Coumadin) can either raise or lower the amount of warfarin in your body. Your provider might need to adjust your dose of the blood thinner and monitor your blood works more closely during treatment.

                        Because of the potential for interactions with efavirenz (Sustiva) and various medications, tell your provider and pharmacist about all the medications you take or plan to take. They can make sure your medications are safe to take together.

                        dosage

                        Efavirenz (Sustiva) dosage forms

                        The average cost for 30 tablets of 600mg of Efavirenz (Sustiva) is $42.58 with a free GoodRx coupon. This is 94.75% off the average retail price of $811.69.
                        capsule
                        Capsule
                        DosageQuantityPrice as low asPrice per unit
                        50mg30 capsules$57.76$1.93
                        200mg30 capsules$319.66$10.66
                        600mg30 capsules$42.58$1.42
                        tablet
                        Tablet
                        DosageQuantityPrice as low asPrice per unit
                        600mg30 tablets$42.58$1.42

                        Typical dosing for Efavirenz (Sustiva)

                        • Adults: The typical dose is 600 mg by mouth once daily at bedtime on an empty stomach.

                        • Children (ages 3 months and older who weigh at least 7.7 lbs): Your child's provider will determine the dose based on your child's body weight. Typically, dosage ranges from 100 mg to 600 mg by mouth once daily at bedtime on an empty stomach.

                        interactions

                        Interactions between Efavirenz (Sustiva) and other drugs

                        Efavirenz (Sustiva) may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Efavirenz (Sustiva). Please note that only the generic name of each medication is listed below.

                        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.

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                        How much does Efavirenz (Sustiva) cost?

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                        contraindications-icon

                        Efavirenz (Sustiva) contraindications

                        Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Efavirenz (Sustiva) will not be safe for you to take.
                        alternatives

                        What are alternatives to Efavirenz (Sustiva)?

                        There are a number of medications that your doctor can prescribe in place of Efavirenz (Sustiva). Compare a few possible alternatives below.
                        Efavirenz (Sustiva)
                        Used for:
                        • Treatment of HIV infection in people ages 3 months and older

                        $42.58 Lowest GoodRx priceView Prices
                        Used for:
                        • HIV infection

                        $34.09 Lowest GoodRx priceView Prices
                        Used for:
                        • Treatment of HIV-1 infection in people 2 years and older, weighing at least 30 pounds, with an HIV viral load of less than 100,000 copies/mL and who haven't taken HIV medications before

                        • Short-term treatment of HIV-1 infection in certain people ages 12 years and older, weighing at least 77 pounds, who are planning to start or planning to miss a dose of Cabenuva (cabotegravir / rilpivirine)

                        $1445.30 Lowest GoodRx priceView Prices
                        images

                        Efavirenz (Sustiva) images

                        Yellow Oblong H And 4 - Efavirenz 600mg Tablet
                        This medicine is Yellow, Oblong Tablet Imprinted With "H" And "4".Yellow Oblong H And 4 - Efavirenz 600mg Tablet
                        Yellow Oblong H And 4 - Efavirenz 600mg Tablet
                        This medicine is Yellow, Oblong Tablet Imprinted With "H" And "4".Yellow Oblong H And 4 - Efavirenz 600mg Tablet

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                        References

                        Best studies we found

                        Centers for Disease Control and Prevention. (2018). Updated guidelines for antiretroviral postexposure prophylaxis after sexual, injection drug use, or other nonoccupational exposure to HIV—United States, 2016.

                        Centers for Disease Control and Prevention. (2022). What is PEP?

                        Centers for Disease Control and Prevention. (2023). Facts about neural tube defects.

                        View All References (6)

                        Clinical Info HIV.gov. (n.d.). Immune reconstitution inflammatory Syndrome (IRIS).

                        Clinical Info HIV.gov. (n.d.). Non-nucleoside reverse transcriptase inhibitor (NNRTI).

                        Clinical Info HIV.gov. (n.d.). Reverse transcriptase (RT).

                        HIVinfo.NIH.gov. (2021). HIV treatment – Drug resistance.

                        Rising Pharma Holdings, Inc. (2022). Efavirenz - efavirenz capsule [package insert]. DailyMed.

                        Thapa, S., et al. (2023). Immune reconstitution inflammatory syndrome. StatPearls.

                        GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.
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