Truvada is a combination medication that contains emtricitabine and tenofovir disoproxil fumarate. Truvada is used with other antiretroviral agents as a part of antiretroviral therapy (ART) for HIV-1 in children and adults who weigh at least 37 pounds (17 kg).
Although it is not a cure for HIV, when taken as directed, it allows for the virus to be suppressed. This prevents further transmission of HIV and allows an individual’s immune system to improve through increasing CD4 cell counts and decreasing viral load.
Truvada comes in several different doses. The dosage an individual takes may vary based on their age, weight, other medical conditions, and whether or not they are using Truvada for the treatment of HIV-1 with other HIV medications or on its own for PrEP.
Truvada for PrEP
Truvada is also used for HIV-1 pre-exposure prophylaxis (PrEP) along with safer sex practices to reduce the risk of sexually acquired HIV. Individuals taking Truvada for PrEP should be HIV-negative and should be at least 77 pounds (35 kg). PrEP is intended to be used by individuals who may be at an increased risk of acquiring HIV, including those who have a sexual partner with HIV.
How effective is Truvada when used for PrEP?
When taken as directed, PrEP may decrease the risk of HIV transmission by 92 percent in men who have sex with men and 90 percent in heterosexual couples. PrEP may also reduce the risk of HIV transmission in individuals who inject drugs by 70 percent, and in all situations, these numbers may increase or decrease based on how effectively and consistently PrEP is taken. When an individual is taking PrEP, they must follow-up with a healthcare provider every few months.1-3
Ingredients in Truvada
The main ingredients in Truvada are emtricitabine and tenofovir disoproxil fumarate. Both medications are nucleoside reverse transcriptase inhibitors (NRTIs).
How does Truvada work?
Truvada is a combination of two NRTI medications. These medications stop the reverse transcription step of the HIV life cycle. Normally, HIV uses its reverse transcriptase enzyme to build a strand of DNA from its original RNA form. In order to do this, it uses genetic building blocks called nucleosides that come from the host cell. These nucleosides are strung together one at a time, like beads on a string, to create the final DNA product.
NRTIs act as nucleoside mimics that stop the DNA-building process. NRTIs look like normal nucleosides, except they’re missing a special chemical group on one side. Without this group, the reverse transcriptase enzyme is unable to attach more nucleosides to the chain after them.
Possible side effects
When taken as treatment for HIV-1, the most common adverse reactions include: 5
- Diarrhea
- Nausea
- Fatigue
- Headache
- Dizziness
- Depression
- Insomnia
- Abnormal dreams
- Rash
The most common side effects of Truvada used for PrEP include, but are not limited to:5
- Headache
- Abdominal pain
- Weight loss
These are not all the possible side effects of Truvada. Talk to your doctor about what to expect when taking Truvada. You also should call your doctor if you have any changes that concern you when taking Truvada.
Things to note
Truvada has a boxed warning, the strictest warning from the US Food and Drug Administration (FDA). It has this warning because of the possibility of serious side effects as described below.
When used for PrEP, the individual taking Truvada must be HIV-negative. If a previously HIV-negative individual becomes HIV-positive while taking Truvada, they must begin a new treatment regimen, as Truvada on its own is not indicated for HIV treatment.
Individuals taking Truvada for PrEP must get tested for HIV every few months, as well as tested for other sexually transmitted infections. Truvada for PrEP is most effective when combined with safer sex methods such as using latex or polyurethane condoms during sex.
When used for PrEP, Truvada should only be prescribed to individuals who have confirmed negative HIV status just before starting the medication and periodically during its use. It's important to be aware that drug-resistant HIV-1 variants have been found in individuals using Truvada for PrEP after undetected acute HIV-1 infection. Therefore, Truvada should not be initiated for a PrEP indication if there are signs or symptoms of acute HIV infection.
Avoid using Truvada in combination with medications that contain emtricitabine or tenofovir disoproxil fumarate, such as Atripla, Complera, Emtriva, Stribild, and Viread. Additionally, do not use Truvada with drugs that contain lamivudine. It is important not to administer Truvada together with Hepsera.
Bone mineral density (BMD) may decrease in individuals taking this medication. It is recommended to evaluate the BMD of patients with a history of pathologic fractures or other risk factors for osteoporosis or bone loss. Additionally, there have been reports of redistribution or accumulation of body fat in individuals receiving antiretroviral therapy, including this medication.
When didanosine is used together with tenofovir disoproxil fumarate, caution is advised as it can increase the concentrations of didanosine. Monitoring for signs of didanosine toxicity, such as pancreatitis or neuropathy, is recommended. Depending on the severity, dose reductions or discontinuation of didanosine may be necessary.
When atazanavir is coadministered with Truvada, atazanavir concentrations may decrease and tenofovir concentrations may increase. It is recommended to use atazanavir with Truvada only when ritonavir is also included, and to monitor for signs of tenofovir toxicity.
Concurrent use of lopinavir/ritonavir with tenofovir can increase tenofovir concentrations. Regular monitoring for signs of tenofovir toxicity is advised.
As with any medication, there are several very rare but serious risks that need to be considered before taking Truvada. Your healthcare provider can help determine what issues you may be at risk for and help determine what treatment options are the safest for you. It’s also important to remember that the risk of one or more of these issues occurring is low, and the benefits of preventing the spread of the virus often greatly outweigh the risks.
Several of these rare but serious side effects of Truvada include liver issues and an increase of lactic acid in the blood (lactic acidosis). Signs of liver issues include, but are not limited to:
- Dark-colored urine
- Loss of appetite
- Nausea
- Yellowing of the whites of the eyes or skin
- Light-colored bowel movements
- Pain or tenderness on the right side of your stomach
Signs of lactic acidosis include, but are not limited to:
- Trouble breathing
- Feeling cold, especially in the limbs
- Dizziness or lightheadedness
- Feeling tired or weak
- Muscle pain
- Nausea and vomiting
- Irregular or fast heartbeat
If you have hepatitis B virus and start taking Truvada, your hepatitis B may get worse. On rare occasions, Truvada may cause new or worsening kidney issues. This includes an increased risk of kidney failure. Your healthcare provider will need to monitor your kidney function before you start and while taking Truvada. Rarely, bone issues may happen while taking Truvada, including, but not limited to, bone pain, thinning, or softening. These problems may lead to bone fractures.
Contact your healthcare provider as soon as possible if you experience psychiatric issues such as depression or mood changes. There are several medications that should not be taken with Truvada. It is important to tell your doctor about any and all medications you are taking to ensure you are taking Truvada safely.
Before starting Truvada, tell your doctor if you:
- Have or previously had hepatitis B virus
- Have a history of liver or kidney problems
- Have a history of bone problems
- Have a history of mental illness, depression, or suicidal thoughts
- Are pregnant or planning to become pregnant
- Are breastfeeding or planning to breastfeed
- Are taking any over-the-counter vitamins, supplements, medicines, or herbal remedies
- Are on any other medications or are about to start any other medications, including hormonal birth control or medications for hepatitis viruses
Truvada may cause a condition called IRIS (immune reconstitution inflammatory syndrome). IRIS occurs when an individual’s immune system gets stronger after being weak and responds aggressively to previously hidden infections. This heightened response may make the person fighting the infection feel worse.
Alert your healthcare provider immediately if you begin to have new symptoms after taking Truvada. These are not all the possible side effects of Truvada for PrEP. Patients should talk to their doctor about what to expect with treatment with Truvada for PrEP. It is important to take your medication exactly as prescribed: do not stop or change your Truvada dosage without talking to your healthcare provider first.