How long can an oral salvia drug test detect the use of marijuana when only used very little?

About a week: Occasional cannabis use if detectable for a week while chronic use can be detected up to a month.

Depends on use.: It depends on how often you use it. If you used it only once it can be detected by blood for 12-24 hours while it is detected in urine from 1-7 days. With regular use it can be detected in blood for 2-7 days and in urine anywhere from 1-100 days even if a heavy user. Age, height, weight, metabolism all are considered factors. Saliva can be 12-24 hours.