Lab result explainedInflammationLast updated November 11, 2026

HIV test: window periods, 4th generation results, and what a reactive or negative result means

HIV test · HIV-1/HIV-2 antigen/antibody immunoassay (4th generation) with reflex to differentiation and HIV-1 RNA · reported in Screening and confirmatory tests: qualitative (non-reactive/negative, reactive/positive, indeterminate). HIV RNA viral load: copies/mL. CD4 count: cells/mm³ (same as cells/µL)

An HIV test looks for evidence of the human immunodeficiency virus in blood or oral fluid: the virus's own genetic material (RNA), a viral protein called p24 antigen, or the antibodies your immune system makes against it. The standard test in US laboratories today is the fourth-generation HIV-1/HIV-2 antigen/antibody combination immunoassay, which detects both p24 and antibodies and is reported as non-reactive (negative) or reactive. A reactive screen is never a diagnosis on its own; it is automatically followed by a confirmatory antibody differentiation test and, if needed, an HIV RNA test.

The single most important idea for reading a result is the window period, the time between an exposure and the point at which a test can reliably detect infection. A nucleic acid test (NAT, or HIV RNA) detects most infections 10 to 33 days after exposure; a fourth-generation laboratory test 18 to 45 days; a rapid fingerstick antigen/antibody test 18 to 90 days; and antibody-only tests, including the oral-fluid home test, 23 to 90 days. A negative result taken inside the window does not rule infection out and is repeated once the window has closed.

The CDC recommends that everyone aged 13 to 64 be tested at least once, that people with ongoing risk test at least yearly, and that anyone taking pre-exposure prophylaxis (PrEP) test every 2 to 3 months. Modern tests are very accurate: a fourth-generation assay detects more than 99.7 percent of established infections and gives a false-reactive result in roughly 1 to 5 of every 1,000 uninfected people, which is why the confirmatory step is built in. With treatment, a person with HIV whose viral load stays under 200 copies/mL cannot pass the virus on through sex.

HIV test at a glance

  • What it is: a screen for HIV infection, usually a fourth-generation blood test that detects p24 antigen plus HIV-1 and HIV-2 antibodies; reported as non-reactive or reactive.
  • Normal result: non-reactive (negative). It is conclusive only once you are past the window period for that test: 45 days for a 4th generation lab test, 90 days for rapid fingerstick and home antibody tests, 33 days for an HIV RNA test.
  • Reactive (positive) screen: needs confirmation with an HIV-1/HIV-2 differentiation test and, if that is negative or indeterminate, an HIV RNA test. A reactive screen with negative confirmation is a false positive, which happens in about 1 to 5 per 1,000 tests.
  • How long results take: rapid and home tests 1 to 30 minutes; laboratory tests 1 to 3 days, with confirmatory results in up to a week; HIV RNA 2 to 7 days.
  • Possible exposure in the last 72 hours: post-exposure prophylaxis (PEP) is time-critical, so go to an emergency department or urgent care now rather than waiting to test.
  • Next step after a confirmed positive: viral load, CD4 count and resistance testing, and antiretroviral treatment started within days; a sustained viral load under 200 copies/mL means the virus is not transmitted sexually.

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What HIV test measures

After HIV enters the body it replicates in lymphoid tissue for about a week before anything is measurable in blood. HIV RNA appears first and is detectable by nucleic acid testing from around day 10. The p24 capsid protein follows at about day 14 to 18, peaks around weeks 3 to 4, then becomes undetectable as antibodies bind it. IgM antibodies appear at roughly 3 weeks and IgG antibodies by 4 to 6 weeks, after which antibody remains positive for life, treated or not. Each generation of test picks up a different point on this curve, which is why window periods differ.

The fourth-generation assay (also called an Ag/Ab combo test) uses antibodies against p24 plus synthetic HIV-1 and HIV-2 antigens to capture both the viral protein and your antibodies in one reaction, reporting reactive or non-reactive against a signal cutoff. Third-generation tests detect IgM and IgG only; most rapid oral-fluid tests detect mainly IgG and have the longest window. Nucleic acid tests amplify viral RNA and are used for very recent exposures, to resolve indeterminate results, for infants under 18 months (who carry maternal antibody), and as the quantitative viral load once infection is confirmed.

Under the CDC and Association of Public Health Laboratories algorithm used since 2014, a reactive Ag/Ab screen is automatically followed by an HIV-1/HIV-2 antibody differentiation immunoassay on the same sample. If the differentiation test is positive, the diagnosis is confirmed and the type (HIV-1 or HIV-2) is reported. If it is negative or indeterminate, an HIV-1 RNA test decides: RNA detected means acute infection; RNA not detected means the screen was a false positive. Rapid tests done in clinics, pharmacies or at home are screening tests only, and a preliminary positive always goes to a laboratory for this same confirmation.

Normal range for HIV test

Reference ranges vary between labs and by age, sex and pregnancy. Use the range printed on your own report.

GroupTypical range (Screening and confirmatory tests: qualitative (non-reactive/negative, reactive/positive, indeterminate). HIV RNA viral load: copies/mL. CD4 count: cells/mm³ (same as cells/µL))Notes
Ag/Ab screen (4th generation): non-reactiveNegativeNo p24 antigen or HIV antibody detected. Conclusive if the last possible exposure was more than 45 days earlier (laboratory test) or 90 days earlier (rapid fingerstick); otherwise repeat at the end of the window.
Ag/Ab screen: reactivePreliminary positive, confirmation pendingThe lab automatically runs an HIV-1/HIV-2 differentiation test. This is not a diagnosis until the confirmatory result is back, usually within a few days.
Differentiation immunoassay: HIV-1 positive or HIV-2 positiveConfirmed HIV infectionHIV-1 causes more than 99 percent of US infections. HIV-2 is seen mainly in people with ties to West Africa, needs different drug choices and is not measured by standard viral-load tests, so the type matters.
Differentiation negative or indeterminate, HIV-1 RNA detectedAcute (very recent) HIV infectionAntibodies have not fully formed yet. Viral load is typically very high (often over 100,000 and sometimes over 1 million copies/mL), which makes this the most infectious stage.
Differentiation negative, HIV-1 RNA not detectedFalse-positive screen; no HIV infectionOccurs in roughly 1 to 5 per 1,000 uninfected people screened. No further action is needed unless a new exposure occurs, although some clinicians repeat the screen in 2 to 4 weeks.
Rapid or home antibody test (fingerstick or oral fluid)Negative, or preliminary positiveWindow period up to 90 days. A preliminary positive needs a laboratory Ag/Ab test with confirmation. The oral-fluid home test misses about 1 in 12 infections in self-testers according to its FDA labeling.
HIV RNA viral load (after diagnosis)Not detected or below 20–50 copies/mL (undetectable); under 200 (virally suppressed); 200–1,000 (low-level viremia); above 100,000 (high)Under 200 copies/mL sustained for 6 months means the virus cannot be passed on sexually (undetectable = untransmittable). Untreated infection usually runs from 10,000 to several hundred thousand copies/mL.
CD4 T-cell count (after diagnosis)500–1,500 cells/mm³ normal; 200–499 reduced; under 200 defines AIDSMeasures immune damage rather than the virus. Treatment is started at any CD4 count; the count usually recovers over 1 to 3 years on suppressive therapy.

Reactive (positive) HIV test

A reactive screening result means the assay detected HIV antigen, antibody or both above its cutoff. It is not yet a diagnosis. In clinics serving people at higher risk, most reactive screens are confirmed; in routine low-prevalence screening, such as prenatal testing or an insurance physical, as many as half of reactive screens turn out to be false positives once the differentiation test and RNA test are run. That is not a flaw in the system; it is why the confirmation step exists, and the complete result normally arrives within a few days.

A confirmed positive means you have HIV infection. It does not mean you have AIDS, which is a late stage defined by a CD4 count under 200 cells/mm³ or an AIDS-defining illness; most people diagnosed today are years away from that point. Current guidelines recommend starting antiretroviral treatment as soon as possible, ideally within the same week, regardless of CD4 count. On consistent treatment the viral load falls below detection within 3 to 6 months, life expectancy approaches that of people without HIV, and once the viral load has been under 200 copies/mL for six months the virus is not transmitted through sex.

An acute-infection pattern (reactive Ag/Ab, negative or indeterminate differentiation test, HIV-1 RNA detected) means infection within the past few weeks. The viral load is usually extremely high at this stage, so recent partners need to be told and offered testing, and PEP if their exposure was within 72 hours. An indeterminate result with RNA not detected is usually a false positive, but if the exposure was recent the test is repeated in 2 to 4 weeks. Anyone newly diagnosed is also offered testing for syphilis, hepatitis B and C, chlamydia, gonorrhea and tuberculosis, which commonly travel together.

Common causes

  1. Established HIV-1 infection

    The usual reason for a confirmed positive. Antibodies to HIV-1 remain detectable for life, so the test stays positive whether infection was acquired months or decades ago, and whether or not treatment has made the viral load undetectable.

  2. Acute (recent) HIV infection

    Infection within the last 2 to 6 weeks shows up as p24 antigen or RNA before antibodies are complete. Between half and 90 percent of people have a flu-like illness at this stage, and the viral load is at its lifetime peak.

  3. HIV-2 infection

    A related virus that progresses more slowly, found mainly in West Africa and in people with ties there. Some antiretroviral drugs (the NNRTI class) do not work against it and standard viral-load assays do not measure it, so the differentiation result changes management.

  4. False-reactive screen after vaccination or an acute viral illness

    Influenza and other vaccines in the preceding few weeks, infectious mononucleosis, acute hepatitis, dengue and other viral infections can produce cross-reacting antibodies that trip the screening assay. Confirmation is negative and no HIV infection is present.

  5. False-reactive screen in autoimmune disease, pregnancy and other antibody-rich states

    Lupus, rheumatoid arthritis, multiple pregnancies, hemodialysis, recent transfusion or immunoglobulin, chronic liver disease and multiple myeloma all raise the chance of a false-reactive screen, which is why screening specificity is quoted at 99.5 to 99.9 percent rather than 100.

  6. Participation in an HIV vaccine trial

    Experimental vaccines induce antibodies that look like infection on antibody tests (vaccine-induced seropositivity). RNA testing distinguishes it, and trial participants are given documentation for this reason.

  7. Infants born to mothers with HIV

    Maternal IgG crosses the placenta and makes antibody tests positive for up to 18 months in uninfected babies. Infants are tested with HIV RNA or DNA in the first days of life, at 1 to 2 months and at 4 to 6 months instead.

  8. Breakthrough infection on PrEP or after PEP

    Antiretrovirals taken during early infection blunt antigen and antibody production, producing weakly reactive or indeterminate screens and delayed seroconversion. This is why PrEP monitoring now includes an HIV RNA test alongside the Ag/Ab test.

  9. Sample mix-up or clerical error

    Rare, but a confirmed positive in someone with no plausible exposure justifies a fresh sample drawn and labeled in your presence; most clinics do this routinely before giving a new diagnosis.

Symptoms that can go with it

  • Often none: most people with HIV feel entirely well for years, which is why testing rather than symptoms identifies infection
  • Acute HIV (2 to 4 weeks after exposure): fever, sore throat, a widespread non-itchy rash, swollen lymph nodes, muscle and joint aches, mouth ulcers, headache and night sweats, lasting 1 to 2 weeks
  • Persistent swollen lymph nodes in the neck, armpits or groin lasting more than 3 months
  • Recurrent oral thrush, shingles at a young age, or frequent and severe cold sore or genital herpes outbreaks
  • Unexplained weight loss of more than 10 percent, diarrhea lasting more than a month, or drenching night sweats
  • Persistent dry cough and breathlessness on exertion, which can signal Pneumocystis pneumonia when the CD4 count is low
  • Memory or concentration problems, numbness in the feet, or purple skin patches (Kaposi sarcoma) in advanced disease

Non-reactive (negative) HIV test

A non-reactive result means no HIV antigen or antibody was found in your sample at the level the assay can detect. If your last possible exposure was more than 45 days before a laboratory fourth-generation test, or more than 90 days before a rapid or home antibody test, the result is conclusive: you do not have HIV. The CDC treats a negative laboratory Ag/Ab test at 45 days as definitive. Some clinics still offer a repeat at 90 days after a very high-risk exposure, and after a course of PEP the test is repeated at 4 to 6 weeks and again at 3 months after the exposure.

A negative test inside the window period is reassuring but not final. HIV RNA testing can be added for an exposure within the past 10 to 33 days, which is particularly useful when there are symptoms of acute infection. Taking PrEP or PEP can delay the appearance of antigen and antibody, so people on PrEP are monitored with both an Ag/Ab test and an HIV RNA test every 2 to 3 months. A negative result says nothing about future exposures, does not confer protection, and is not a substitute for a partner's own test.

Common causes

  1. Testing inside the window period

    The commonest reason for a falsely reassuring negative. A 4th generation lab test detects half of infections by about 18 days and 99 percent by 44 to 45 days; antibody-only and oral-fluid tests take up to 90 days.

  2. Antibody-only or oral-fluid test used for a recent exposure

    Oral fluid contains far less antibody than blood and no p24 antigen, so home oral tests have the longest window and the lowest sensitivity; an exposure 3 to 8 weeks ago needs a laboratory Ag/Ab or RNA test.

  3. PrEP or PEP suppressing early viral replication

    Antiretrovirals taken around the time of infection can keep RNA, antigen and antibody below detection for weeks to months. Anyone who has taken PrEP or PEP is retested after stopping, with RNA testing added.

  4. Rare assay blind spots

    Unusual strains (HIV-1 group O or N) on older assays, HIV-2 on HIV-1-only tests, and people who cannot make antibodies (agammaglobulinemia) account for a tiny number of missed infections. Modern combination assays cover HIV-1 groups M and O and HIV-2.

  5. Sample or labeling error

    A negative result that does not fit the clinical picture, for example a very low CD4 count or an AIDS-defining illness, is repeated on a fresh sample with an RNA test.

Symptoms that can go with it

  • None; a negative result is the expected finding and causes no symptoms
  • Fever, rash, sore throat and swollen glands 2 to 4 weeks after an exposure, even with a negative antibody test, should prompt an HIV RNA test, since symptoms can appear before antibodies do

Read it alongside

  • HIV-1 RNA (viral load) — confirms acute infection when antibodies are not yet formed, and after diagnosis tracks treatment: the goal is under 200 copies/mL, ideally undetectable.
  • CD4 count and CD4 percentage — measures immune damage; under 200 cells/mm³ defines AIDS and triggers prophylaxis against opportunistic infections.
  • HIV genotype (drug-resistance) test — done on the first positive sample so that treatment is chosen to work against the strain you carry.
  • Syphilis screen (RPR or treponemal antibody) — HIV and syphilis are frequently acquired together, and syphilis can run an aggressive course in people with HIV.
  • Hepatitis B surface antigen, surface antibody and core antibody — co-infection changes drug choice, and non-immune people are vaccinated.
  • Hepatitis C antibody with reflex RNA — shared risk factors; curative hepatitis C treatment is available and prioritized in people with HIV.
  • Chlamydia and gonorrhea NAAT from urine, throat and rectum — recommended at diagnosis and every 3 to 6 months for people on PrEP or with new partners.
  • Creatinine and eGFR, and a pregnancy test — baseline kidney function before PrEP or treatment (tenofovir is cleared by the kidney), and pregnancy status, which changes the urgency of treatment.

What usually happens next

  1. A negative result inside the window period is repeated at the end of the window: 45 days after the exposure for a laboratory Ag/Ab test, 90 days for a rapid or home test. Ask which test you had, because the dates differ.
  2. A reactive screen is confirmed on the same sample within a few days; do not repeat a home test to 'check', and expect the clinic to draw a second sample before giving a final diagnosis.
  3. A confirmed positive leads to same-week linkage to HIV care: viral load, CD4 count, resistance testing, baseline hepatitis and syphilis tests, and antiretroviral treatment started as soon as possible, often the same day. Partner notification services can tell recent partners anonymously.
  4. An exposure within the past 72 hours is an emergency for PEP (a 28-day course of antiretrovirals); testing happens at baseline, 4 to 6 weeks and 3 months after the exposure.
  5. Ongoing risk is the trigger to discuss PrEP, which cuts the risk of sexual acquisition by about 99 percent when taken as prescribed, with Ag/Ab plus RNA testing every 2 to 3 months while on it.
  6. Questions worth asking: which test was used and its window period, whether an RNA test is appropriate, how results will be delivered, and whether anonymous or confidential testing options matter to you.

Diet, lifestyle and natural levers with evidence

What can move HIV test once the cause is known. Nothing here replaces finding the cause.

Match the test to the time since exposure

Strong evidence

Nothing you eat or do speeds up seroconversion; timing is the only lever on a negative result. In a CDC analysis of seroconversion panels, 4th generation lab assays turned reactive at a median of 18 days and in 99 percent of people by 44 days, antibody-only assays at a median of 23 days and 99 percent by about 90 days, and RNA tests from day 10. Testing at 45 days with a lab Ag/Ab test, or adding an RNA test for an exposure in the past 2 to 4 weeks, resolves nearly all uncertainty.

If you take PrEP or have taken PEP, ask for an HIV RNA test too

Strong evidence

Antiretrovirals taken around the time of an exposure blunt the antigen and antibody response, and case series of PrEP breakthrough infections show indeterminate or delayed results for weeks to months. The CDC's 2021 PrEP guideline therefore recommends an Ag/Ab test plus HIV-1 RNA before starting PrEP, every 3 months on oral PrEP and every 2 months on injectable cabotegravir, and again 1 to 3 months after stopping.

Do not stop PrEP to 'clear' a result; starting or stopping PrEP around an undetected infection is how drug resistance develops.

Know what produces a false-reactive screen

Moderate evidence

Vaccination (particularly influenza) in the previous 2 to 4 weeks, acute viral illnesses such as mononucleosis, autoimmune diseases, pregnancy and recent immunoglobulin or transfusion each modestly raise the chance of a reactive screen that fails confirmation. No food, supplement, herb, alcohol or recreational drug alters an HIV antigen, antibody or RNA result in either direction, so a true positive cannot be made negative and a negative cannot be made positive by anything you take.

After a positive result, uninterrupted antiretroviral treatment is the only lever that moves the viral load

Strong evidence

In HPTN 052, early treatment cut transmission to partners by 93 percent, and in the PARTNER and PARTNER2 studies there were zero linked transmissions across roughly 77,000 condomless sex acts when the partner with HIV had a viral load under 200 copies/mL. Adherence of 90 to 95 percent of doses is what keeps the viral load suppressed; no diet or supplement has any measurable effect on it.

St. John's wort cuts blood levels of many antiretrovirals (indinavir by about 57 percent in one study) and is contraindicated; calcium, magnesium, iron and zinc supplements and antacids bind integrase inhibitors and must be separated by several hours. Tell your HIV clinician about every supplement.

When to see a clinician promptly

  • A possible exposure within the past 72 hours (condomless sex with a partner of unknown or positive status who is not virally suppressed, shared injecting equipment, a needlestick, sexual assault): PEP works best within hours and is not offered after 72 hours, so go to an emergency department or urgent care today rather than waiting to test.
  • A reactive or preliminary positive result on any test, to arrange confirmatory testing and, if confirmed, same-week linkage to HIV care.
  • Fever, rash, sore throat and swollen glands 2 to 4 weeks after a possible exposure, even if a test was negative: ask for an HIV RNA test.
  • A confirmed positive test in pregnancy or while breastfeeding: treatment reduces transmission to the baby from about 25 percent to under 1 percent, and the earlier it starts the better.
  • Known HIV with fever lasting more than a week, breathlessness, severe headache with a stiff neck, confusion, new visual loss or rapid weight loss: possible opportunistic infection, needs same-day assessment.
  • Difficulty coping or thoughts of self-harm after a new diagnosis: HIV services, counselors and crisis lines offer same-day support, and the outlook with treatment is a normal lifespan.

Frequently asked questions

How long after exposure can an HIV test detect it?

It depends on the test. An HIV RNA (nucleic acid) test can detect infection 10 to 33 days after exposure, a fourth-generation antigen/antibody laboratory test 18 to 45 days, a rapid fingerstick antigen/antibody test 18 to 90 days, and antibody-only tests including the oral-fluid home test 23 to 90 days. A negative result is conclusive only once the upper end of that window has passed; before that it is reassuring but needs repeating.

What is a 4th generation HIV test?

A blood test that detects both HIV antibodies (IgM and IgG against HIV-1 and HIV-2) and the p24 antigen, a viral protein that appears in blood about 2 weeks after infection, several weeks before antibodies are reliable. Adding p24 shortens the window period to 18 to 45 days and catches acute infection, when people are most infectious. It is the standard laboratory screening test in the United States and the one guidelines recommend.

How long does an HIV test take to come back?

Rapid fingerstick and oral-fluid tests give a result in 1 to 30 minutes. Laboratory antigen/antibody tests usually take 1 to 3 business days; if the screen is reactive, the confirmatory differentiation test is run automatically on the same sample and the full result typically takes 3 to 7 days. HIV RNA tests take 2 to 7 days. Mailed home-collection kits take about a week including shipping.

What does a reactive HIV test mean?

Reactive means the screening assay detected antigen or antibody above its cutoff. It is a preliminary result, not a diagnosis. The laboratory runs an HIV-1/HIV-2 differentiation test and, if needed, an RNA test to decide whether it reflects true infection, acute infection or a false positive. In higher-risk settings most reactive screens are confirmed; in routine low-risk screening a large share are not, so wait for the confirmed result before drawing conclusions.

How common is a false positive HIV test?

Screening assays have a specificity of about 99.5 to 99.9 percent, so roughly 1 to 5 of every 1,000 people without HIV get a reactive screen. Because HIV is uncommon in the general population, that can mean up to half of reactive screens in low-risk groups are false positives, all of which are sorted out by the confirmatory test within days. A confirmed positive (reactive screen plus positive differentiation test or detectable RNA) is essentially never a false positive.

Is a negative HIV test at 6 weeks conclusive?

With a laboratory fourth-generation antigen/antibody test, a negative result at 6 weeks (42 days) is very close to conclusive, and the CDC considers it definitive at 45 days. If a rapid fingerstick or oral-fluid antibody test was used, or you took PEP or PrEP around the exposure, you need a repeat at 90 days. For a single exposure without PEP, a negative lab Ag/Ab test at 45 days or a negative RNA test at 33 days is enough.

Can I test for HIV at home?

Yes. The FDA-approved oral-fluid self-test gives a result in 20 to 40 minutes but is antibody-only, so it has a 90-day window and misses about 1 in 12 infections in self-testers; a positive is preliminary and needs lab confirmation. Mailed home-collection kits (a fingerstick blood spot sent to a laboratory) use a fourth-generation test and are as accurate as a clinic draw. Free self-test kits are available through many health departments.

Does PrEP affect HIV test results?

It can. If HIV is acquired while taking PrEP, or PrEP is started during an undetected acute infection, the drugs suppress the virus enough to blunt p24 antigen and antibody production, giving weakly reactive, indeterminate or delayed results. That is why PrEP monitoring includes an HIV RNA test alongside the antigen/antibody test every 2 to 3 months, and why you should never start PrEP without a negative test from the previous 7 days.

References

  1. HIV screening test. MedlinePlus, US National Library of Medicine (2024)View source
  2. Getting tested for HIV. Centers for Disease Control and Prevention (2024)View source
  3. Branson BM, Owen SM, Wesolowski LG, et al.. Laboratory testing for the diagnosis of HIV infection: updated recommendations. Centers for Disease Control and Prevention and Association of Public Health Laboratories (2014)
  4. Delaney KP, Hanson DL, Masciotra S, Ethridge SF, Wesolowski L, Owen SM. Time until emergence of HIV test reactivity following infection with HIV-1: implications for interpreting test results and retesting after exposure. Clinical Infectious Diseases (2017)
  5. US Preventive Services Task Force. Screening for HIV infection: US Preventive Services Task Force recommendation statement. JAMA (2019)
  6. Preexposure prophylaxis for the prevention of HIV infection in the United States, 2021 update: a clinical practice guideline. Centers for Disease Control and Prevention (2021)
  7. Rodger AJ, Cambiano V, Bruun T, et al.. Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): final results of a multicentre, prospective, observational study. The Lancet (2019)
  8. Cohen MS, Chen YQ, McCauley M, et al.. Antiretroviral therapy for the prevention of HIV-1 transmission. New England Journal of Medicine (2016)
  9. Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in adults and adolescents with HIV. US Department of Health and Human Services (2024)
  10. Piscitelli SC, Burstein AH, Chaitt D, Alfaro RM, Falloon J. Indinavir concentrations and St John's wort. The Lancet (2000)
  11. HIV testing. Mayo Clinic (2024)
  12. Human immunodeficiency virus (HIV) infection. Merck Manual Professional Version (2024)

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This page is educational and is not medical advice or a diagnosis. Lab results have to be interpreted together with your history, symptoms and other results by a clinician who knows you. Do not start or stop a supplement to change a lab value before the cause is known.