Better2Know Drug & alcohol testing

Carbohydrate Deficient Transferrin Home Test Kit

A home finger-prick blood test that measures carbohydrate deficient transferrin, a marker used to indicate sustained heavy alcohol consumption over recent weeks.

  • At-home test
  • Subscription available
Sample
Blood
Collection
At-home finger-prick, post to lab
Results in
3 days
Biomarkers
1
Tests for
  • Carbohydrate deficient transferrin

Test specifications

Provider
Better2Know
Sample type
blood
Collection method
at-home finger-prick, post to lab
Turnaround time
3 days
Biomarkers tested
1
At-home test
Yes
Doctor reviewed
No
Gender focus
Both

What's tested

1 biomarker as listed by Better2Know.

Alcohol consumption

  • Carbohydrate deficient transferrin

About this test

Carbohydrate deficient transferrin, or CDT, is a form of the blood protein transferrin that increases when you drink heavily and regularly, typically four or more drinks a day, five or more days a week, for at least two weeks beforehand. It is used as a marker of sustained heavy alcohol intake rather than a one-off drinking session, which makes it different from tests that only detect recent, single-occasion drinking.

This is Better2Know's only CDT test in our catalogue, so we cannot compare its price or depth against a direct peer. What we can say is that £225 for one marker sits above the median price of the toxicology tests we track, and the test measures CDT alone rather than being part of a wider alcohol or liver panel.

The test scores reasonably for clinical depth relative to other toxicology tests we track, and for collection convenience, since you collect the sample yourself at home with a simple finger-prick. It scores poorly on value for money given the single marker, and, like other Better2Know tests in this sheet, on results and follow-up, since your result is not reviewed by a doctor as standard. Better2Know is CQC registered, holds a Trustpilot score of 4.2 from 775 reviews, and has traded since 2008.

Who is it for?

This test suits you if you specifically want to check for signs of sustained heavy drinking over the past few weeks, for example if you are monitoring your own alcohol intake or need evidence of drinking patterns for a personal or professional reason. Because it measures only CDT, it will not tell you about liver damage or other effects of alcohol, and a single reading does not capture occasional heavy drinking outside the detection window.

We do not have a comparable Better2Know CDT test to weigh this one against, so there is no cheaper or deeper in-house alternative to point you to here. If you are concerned about your drinking, speak to a GP, who can advise on wider testing and support.

How it works

You collect a small blood sample yourself with a finger-prick using the kit provided, then post it to Better2Know's laboratory in the prepaid envelope supplied. The sample is analysed for carbohydrate deficient transferrin, with results typically available within three working days of arrival at the lab, viewable through Better2Know's secure online patient area. Results are not reviewed by a doctor as standard.

Pros & cons

Pros

  • Self-collected finger-prick sample, no clinic visit required.
  • Checks for a marker of sustained heavy drinking rather than a single session.
  • Results are available within three working days of the lab receiving your sample.

Cons

  • Tests one marker only, at a price above the toxicology tests we track.
  • No other Better2Know CDT test to compare it against for value.
  • Results are not reviewed by a doctor as standard.

Our editorial score

Compare Health Test Score At-home CDT test for sustained heavy alcohol use
Editorial confidence: 9.0/10

This kit checks carbohydrate deficient transferrin, or CDT, a marker that rises after several weeks of heavy, regular drinking, from a finger-prick sample you collect at home. At £225 it sits above the typical price of the toxicology tests we track, for a single marker. We have no other Better2Know CDT test to compare it with directly, so weigh the price against what one marker tells you before you order.

Score breakdown

  • Clarity and documentation 9.0/10

    The listing publishes a detailed description, the full biomarker list, a stated turnaround, clear collection options, the sample type; it does not state what the report looks like.

  • Clinical depth 7.2/10

    1 biomarkers, placing it in the 44th percentile of toxicology tests we track.

  • Collection convenience 6.0/10

    A finger-prick sample you take at home; results in around 3 days, slower than similar tests.

  • Results and follow-up 3.0/10

    Results are not doctor-reviewed and no consultation is included; the provider does not describe the report format.

  • Trust signals 6.5/10

    Trustpilot 4.2 from 775 reviews; CQC registered; trading 18+ years.

  • Value for money 4.5/10

    £225.00 against a median of £160.00 for the 8 similarly sized toxicology tests we track (+41%).

Calculated 13 September 2026 from the facts we hold about this test and provider, using our published scoring formula. Scores are not hand-edited.

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