Glossary

wasting – loss of lean body mass (muscle loss). A unplanned or unexplained wight loss of more than 5% body weight over six months can be an AIDS-defining illness.

Weight loss and wasting section of the training manual.

T1/2 (half-life) –  the time taken a drug to clear from the highest concentration to half this level. Drugs have different half-lives in different compartments (ie half-life in blood can be different from the half-life inside a cell). It take 5 x the half-live for a drug to be considered cleared.

What happens when you take a drug?

substitution therapy – using a prescription drug, eg methadone or buprenorphine, to stop using heroin.

lipid – medical term for fat. The term ‘blood lipids’ refers to cholesterol and triglyceride levels in blood.

viral load test – a test that detects whether a virus is present (qualatitive) or that measures the amount of virus (quantitative).

This is usually in a sample of blood, but a viral load test can also be used to check viral levels in other samples including genital fluid, semen or spinal fluid.

Results are given as the number of copies of virus in a millilitre of blood (copies/mL).