CDT Test and the DVLA
The CDT test is the most popular test used by the DVLA and courts to check if people have been drinking excessively. It is a blood test that checks for excessive alcohol consumption over the previous 7-14 days. The CDT test can be done at the laboratory in London, or by post for people living outside London.
PEth Test for Alcohol Misuse
The PEth test is a blood test that checks for excessive alcohol intake over the previous 3-4 weeks.
Blood and Urine Alcohol Tests
These test for the actual presence and amount of alcohol at the time of the test. The result depends on how much the person has drunk in the previous day and how many hours ago. Alcohol is quickly removed from the body so these tests are not as useful as CDT and PEth tests.
This tests for a range of markers of alcohol misuse such as CDT and PEth, as well as the effects on the liver.
Liver Function Blood Test
This checks for damage to the liver from alcohol and drug misuse.