What it measures
Cotinine is the main breakdown product of nicotine. It stays in the blood for longer than nicotine itself, so the test shows nicotine use over the past few days.
Why people test it
- Asked for by some clinics before certain operations or IVF, where being nicotine-free is a condition.
- Used by some insurers and employers to confirm smoking status.
- Checked by people who want to confirm they have stopped smoking or vaping.
Typical range
Reported as detected or not detected, or as a level against a cut-off that separates nicotine users from non-users. Cut-offs vary by lab, and the report shows the lab's own.
Finger-prick or vein?
Offered as a vein draw at a clinic only.
Nicotine patches, gum and vapes produce cotinine too, so the test shows nicotine use of any kind, not only smoking.