1 / 29

Clinical Pharmacokinetics of Alcohol in A CDAT Sample

This study investigates alcohol clearance in patients with alcohol dependence syndrome, indicating first-order kinetics. Clinical implications include potential biological diagnoses and support for drinking reduction therapy.

fcramer
Download Presentation

Clinical Pharmacokinetics of Alcohol in A CDAT Sample

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Clinical Pharmacokinetics of Alcohol in A CDAT Sample Robert Cohen Consultant Addiction Psychiatrist 9.11.2012

  2. Introduction • The way the body handles alcohol is of interest to a number of different groups

  3. Back calculation of alcohol is based on the assumption that the body clears 1 unit of alcohol per hour (zero order kinetics) • Zero order kinetics – same rate of removal however much alcohol left • First order kinetics – the more alcohol in the blood stream, the quicker it is removed

  4. Limited use of alcohol testing in the clinical setting • Result of testing often limited to positive or negative • Though the readings in blood, breath and hair are quantitative and need interpretation

  5. Alcohol testing • Ethanol (ethyl alcohol) or metabolites can be tested in a variety of matrices • Blood • Breath • Sweat • Urine • Hair • Breath alcohol levels closely parallel arterial blood levels Jones & Andersson, For Sci Int 2003;132: 18

  6. The breathalyser • Presents an easy method to test for alcohol levels • Easy to carry out the test • Reliable machinery

  7. This study Kingston CDAT LDASS

  8. The problem of interpreting breathalyser readings • When you take a breathalyser reading, you do not know • When the person last drank • How much they drank • But you may be able to gain an understanding if you know the rate of elimination, • which you can work out by taking multiple readings • This study is a pilot into the start of this question

  9. Methods • 20 consecutive patients who attended for assessment for alcohol / drug problems and whose breathalyser reading was more than 0.00mg/l • Breath alcohol level readings taken at regular intervals • Rate of elimination calculated and compared to the concentration • A composite made of all the readings

  10. absorption distribution clearance

  11. Results • 20 patients at the time of audit • 10 patients used only alcohol (‘alcoholics’) • 10 patients used alcohol on top of methadone (‘drug addicts’) • All met the criteria for a clinical ICD-10 diagnosis of mental and behavioural disorder due to use of alcohol, dependent type (F10.2)

  12. Results - Demographics

  13. Results – Breathalyser Readings

  14. All patients

  15. Alcoholics Drug Addicts

  16. Discussion - findings • Alcohol clearance in people with the alcohol dependence syndrome appears to follow first order kinetics rather than zero order kinetics • This is a composite picture of 20 patients, rather than a full study of individuals over the whole of the pharmacokinetic profile (absorption, distribution and clearance) • This is therefore a pilot study, generating a hypothesis for formal testing

  17. Discussion – clinical implications • Potential to lead to biologically based diagnosis of alcohol dependence • Biological support for drinking reduction as a therapeutic step prior to detoxification • Possible clinical-biological difference between those only using alcohol and alcohol/opiate users

  18. Discussion – clinical implications-1 • If there are clinical differences in the pharmacokinetics of alcohol between dependent people and non-dependent people, this may form the basis of a clinical biologically based test for alcohol use disorder, as opposed to history / rating scale based diagnosis • This is for future investigation

  19. Discussion – clinical implications-2 • This work may eventually elucidate the plasma level of alcohol associated with onset of withdrawal symptoms • However, clinical observations of patients with low plasma levels (e.g., 0.10mg/l) is mixed • Some show withdrawal symptoms • Others do not

  20. Discussion – clinical implications-2 • If withdrawal symptoms drive alcohol consumption in dependent patients then more rapid clearance may be lead to greater consumption, thereby creating a vicious circle • Helping people reduce consumption rather than attain immediate abstinence may therefore be an appropriate clinical goal as a step prior to detoxification

  21. Discussion – clinical implications-3 • There may be a difference between those who are in addition opiate dependent and those who are only dependent on alcohol • There is some evidence for this (Clarke, JSAT 2006; 30:191) • But the findings in this study may also be attributable to the higher level of drinking by opiate dependent patients

  22. Thank you for listening robert.cohen@sept.nhs.uk

More Related