Information on HIV is full of specialist clinical words and phrases that can be difficult to understand. On top of this, it's not always easy for healthcare professionals to explain what they mean.
This glossary is here to help, with simple explanations for the terms you may read or hear. You can download a printable version of this here.
- Adherence
- AIDS (Acquired Immune Deficiency Syndrome)
- Anti-HIV medication
- Asymptomatic
- CD4 protein
- CD4 count
- Class (of medication)
- Combination therapy
- Drug interaction
- Drug resistance
- Entry inhibitors
- Fail (on treatment)
- HAART (Highly Active Anti-Retroviral Therapy)
- HIV (Human Immunodeficiency Virus)
- HIV disease
- Immune system
- Immunosuppression
- Integrase inhibitors
- Lipoatrophy
- Lipodystrophy
- Mutation
- Neuropathy
- NNRTI or Non-Nucleoside Reverse Transcriptase Inhibitor (‘Non-nuke')
- NRTI or Nucleoside Reverse Transcriptase Inhibitor (‘Nuke')
- Progression
- Prophylaxis
- Protease inhibitors (PIs)
- Resistance
- Salvage therapy
- Side effects
- Treatment failure
- Treatment regimen
- Treatment simplification
- Undetectable (viral load)
- Viral load
- Viral strains
Adherence
Taking your medication properly – at the right dose, at the right time, in the right way. This is the most important thing you can do to stay healthy.
Find out more about adherence.
AIDS (Acquired Immune Deficiency Syndrome)
A serious disease of the body's immune system, caused by the progression of HIV. AIDS leaves the body vulnerable to life-threatening infections and cancers.
Anti-HIV medication
Medication that reduces the amount of HIV in your body by helping to prevent the virus from making copies of itself and multiplying.
Find out more about anti-HIV medication.
CD4 protein
A protein on the outside of your infection-fighting cells, that are part of your immune system. HIV invades CD4 proteins to enter and destroy your infection-fighting cells. This damages the immune system and can lead to AIDS.
Find out more about CD4 proteins.
CD4 count
The number of CD4 proteins in a small sample of blood (not your whole body) is a good way to see how strong your immune system is.
In an untreated person with HIV, the CD4 count can be low, and an aim of treatment is to get this higher.
- A normal CD4 count for a person without HIV is about 500–1200 cells/mm3.
- A CD4 count between 500 and 200 shows that your immune system has been slightly damaged by HIV.
- If your CD4 count is below 350, you will need to think about starting treatment.
Find out more about CD4 count.
Class (of medication)
A group of medications that all work in the same way and share common properties.
Find out how anti-HIV medications work.
Combination therapy
Two or more drugs used together to treat an illness.
Find out about combination therapy.
Drug interaction
A change in the body's response to one medication when it's taken with another medication. This may be an increase or decrease in the effect of one or both medications, which may cause them to become harmful.
Find out more about drug interactions.
Drug resistance
Every time HIV copies itself, the virus can change or mutate slightly, affecting its response to medications. Some mutated viruses can multiply even in the presence of a particular anti-HIV medication – this is known as drug resistance.
Find out more about drug resistance.
Highly Active Anti-Retroviral Therapy (HAART)
A phrase sometimes used to describe combination therapy with three or more anti-HIV medications.
Find out more about combination therapy.
HIV (Human Immunodeficiency Virus)
A type of virus, called a retrovirus, which infects CD4 proteins and destroys your infection-fighting cells and can cause AIDS.
Find out more about CD4 cells.
HIV disease
A variety of symptoms that can accompany HIV infection, like recurring fevers, weight loss, skin rashes, swollen areas of the throat, and fungal infection of the mouth and throat.
Immune system
The collection of cells and organs within your body whose job it is to fight infections and illnesses.
Immunosuppression
The reduced ability of the immune system to fight infections and illnesses, which can happen for a number of reasons, e.g. HIV infection.
Lipoatrophy
Loss of body fat from some areas of the body, especially the arms, legs, face, and buttocks. Lipoatrophy is a potential side effect of some anti-HIV medications.
Read more about lipoatrophy here.
Find out about side effects.
Download a side effect diary.
Lipodystrophy
Changes in body shape caused by the loss of fat in some areas and the gain of fat in others, which can result in increased waist size, fat loss in upper legs, fat gain in upper back, and fat loss in the face (especially the cheeks).
Lipodystrophy is a potential side effect of some anti-HIV medications.
Find out about side effects.
Download a side effect diary.
Mutation
By copying itself over and over, the HIV virus in your body can change or mutate. New copies (called viral strains), can have drug resistance, for example.
Find out more about mutation and drug resistance.
Watch an animation of the HIV life cycle.
Neuropathy
HIV infection and certain anti-HIV drugs, can damage nerve cells, causing symptoms like tingling/numbness in the toes and fingers and pain.
NNRTI or Non-nucleoside Reverse Transcriptase Inhibitor (‘Non-nuke')
A class of anti-HIV medication.
Prophylaxis
Treatment to prevent the onset of a disease, or to prevent the recurrence of an infection that has been brought under control.
Salvage therapy
An HIV treatment regimen designed for people who have used many different anti-HIV medications in the past, have experienced treatment failure on at least two anti-HIV regimens, and have extensive drug resistance.
Find out more about drug resistance.
Treatment failure
If you are taking anti-HIV medication, but your viral load is not decreasing, you are said to have experienced treatment failure.
Find out about viral load
Find out about drug resistance
Treatment regimen
The collection or combination of anti-HIV medications you take to improve/maintain your health.
Treatment simplification
If you find it difficult to follow your prescription, your doctor might switch you to medications that are easier to take (e.g. fewer medications and/or medications that are taken less often).
Undetectable (viral load)
Less than 50 copies of HIV in a blood sample is the goal for everyone taking HIV treatment in the UK.
Viral load
The number of copies of HIV per blood sample. In an untreated person with HIV, this can be in the thousands or even millions.
An aim of treatment is to decrease the viral load to undetectable levels.
Viral strains
The many types of a particular virus, which differ in important ways such as being sensitive to medications.
Found out about drug resistance
