When employers think about drug testing, urine testing is often the default. Saliva testing, also called oral fluid testing, is newer by comparison and sometimes misunderstood. Both methods are scientifically valid, but they answer different questions.
Saliva (oral fluid) drug testing detects recent drug use by analyzing trace drug substances present in oral fluid collected from the mouth.
Urine testing, by contrast, detects drug metabolites after the body has processed and begun eliminating them.
That difference matters.
Detection window
Saliva testing is best at identifying recent drug use, often within the past 24 to 48 hours. This makes it useful when timing is important, such as post-incident or reasonable suspicion testing.
Urine testing has a longer detection window, sometimes several days, which makes it effective for identifying prior or historical use rather than immediacy.
Collection process
Saliva testing is directly observed and non-invasive. A small swab is placed between the cheek and gum until enough oral fluid is collected.
Urine testing typically requires a restroom setting and specific collection protocols to reduce the risk of substitution or tampering.
Risk of adulteration
Because saliva collection is observed, opportunities to alter the sample are limited.
Urine testing has long-established safeguards but requires additional controls to protect sample integrity.
Choosing the right method
Neither method is universally better. The right choice depends on what you need to know and when you need to know it.
Next, we’ll break down detection windows and why “how long drugs stay detectable” isn’t a one-size-fits-all answer.
