Does PrEP affect HIV test?

People who take pre-exposure prophylaxis (PrEP) after contracting the virus may experience a delay before HIV tests detect the virus, Reuters Health reports.

What are the 2 most common causes of a false negative result in the HIV test?

Causes of false-negative EIA results include the following:

• Technical error.
• Testing during the window period.
• Decreased host immunoglobulin production such as in a common variable immunodeficiency and advanced AIDS.
• HIV-2 if tests to detect HIV-1 only are used.
• Non–clade-B HIV-1 or type N or O strains of HIV-1.

Can you test negative for HIV but still have it?

A negative result doesn’t necessarily mean that you don’t have HIV. This is due to the window period. If you test again after the window period, have no possible HIV exposure during the window period, and the result comes back negative, you do not have HIV.

Does PrEP show up in blood test?

Lab tests to measure ART success in HIV-positive people rely on measuring the levels of virus directly. For PrEP, the only tests available are expensive blood and urine assays that measure tenofovir levels using mass spectrometry. Tenofovir also only lasts a few days in blood or urine.

Can I test positive while on PrEP?

The presence of antiretrovirals may suppress the immune response and the production of antibodies. Rapid tests and self-tests should not be used to confirm HIV infection in people taking HIV treatment. In the case of repeatedly indeterminate test results in a PrEP or PEP user, seek expert guidance.

What are the side effects of PrEP?

PrEP is safe but some people experience side effects like diarrhea, nausea, headache, fatigue, and stomach pain. These side effects usually go away over time. Tell your health care provider about any side effects that are severe or do not go away. Learn more about side effects from the Truvada® and Descovy® .

What viral load is considered undetectable?

The point at which a viral load is classified as being undetectable may vary across different countries depending on the tests available. But so long as your viral load is under 200 copies per millilitre, you’re considered virally suppressed and unable to pass HIV on.