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A - Z Index

glossary a-z index
F

False NegativeAudio (En español)

A negative test result that incorrectly indicates that the condition being tested for is not present when, in fact, the condition is actually present. For example, a false negative HIV test indicates a person does not have HIV when, in fact, the person is infected with HIV.

See Related Term(s):  False Positive


False PositiveAudio (En español)

A positive test result that incorrectly indicates that the condition being tested for is present when, in fact, the condition is actually not present. For example, a false positive HIV test indicates a person has HIV when, in fact, the person is not infected with HIV.

See Related Term(s):  False Negative


Fanconi SyndromeAudio (En español)

A hereditary or acquired kidney disorder that impairs the reabsorption of electrolytes, glucose, amino acids, and other nutrients into the bloodstream when blood passes through the kidneys. Acquired Fanconi syndrome may be caused by use of certain antiretroviral (ARV) drugs.

See Related Term(s):  Kidneys

Fat Maldistribution

Also Known As: Lipodystrophy

Fatty Liver

Also Known As: Hepatic Steatosis


FetusAudio (En español)

In humans, an infant developing in the uterus (womb) from about the third month of pregnancy until birth.

First-Line TherapyAudio (En español)

The preferred standard treatment for a particular condition. The recommended first-line HIV treatment regimens include antiretroviral (ARV) drugs that are safe and effective for most people with HIV.

Fixed-Dose CombinationAudio (En español)

Two or more drugs contained in a single dosage form, such as a capsule or tablet. An example of a fixed-dose combination HIV drug is Atripla (a combination of efavirenz, emtricitabine, and tenofovir). By reducing the number of pills a person must take each day, fixed-dose combination drugs can help improve adherence to an HIV treatment regimen.

See Related Term(s):  Adherence, Drug Class, Regimen Simplification


Food and Drug Administration (FDA) Audio (En español)

The federal agency responsible for ensuring the safety and effectiveness of drugs, biologics, vaccines, and medical devices. The Food and Drug Administration (FDA) also regulates the manufacture, distribution, and marketing of tobacco products and works to safeguard the nation's blood supply.

FormulationAudio (En español)

Also known as: Drug Formulation

The physical form in which a drug is manufactured or administered. Examples of formulations include tablets, capsules, powders, and oral and injectable solutions. A drug may be available in multiple formulations.

FungusAudio (En español)

A plant-like organism that feeds off a living host organism or dead or decaying material. Examples of fungi include mushrooms, yeast, and mold. People with weakened immune systems, including people with HIV, are at a higher risk for fungal infections than people with healthy immune systems.

Fusin

Also Known As: CXCR4


FusionAudio (En español)

The first of seven steps in the HIV life cycle. HIV binds to the CD4 receptor and a coreceptor (either CCR5 or CXCR4) on the host cell, causing the viral envelope to fuse with the host cell membrane. This fusion allows HIV to release HIV RNA and HIV enzymes, such as reverse transcriptase and integrase, into the host cell.

See Related Term(s):  Fusion Inhibitor, Life Cycle


Fusion InhibitorAudio (En español)

Antiretroviral (ARV) HIV drug class. Fusion inhibitors block the HIV envelope from merging with the host cell membrane (fusion). This prevents HIV from entering the host cell.

See Related Term(s):  Drug Class, Envelope, Fusion