Will a smart start interlock detect anything besides alcohol?

The Smart Start System has many problems. For instance, once a month you are supposed to have the device in for a compliance check. compliance check. That check tests for device tampering or intoxication. There is supposed to be a day or two turn around time for the results of this calibration because there is about a 15 day window to challenge the results of this calibration. Unfortunately, some people have argued that the company was delaying the results of this calibration unnecessarily past this window date so the results could not be challenged to insure the accuracy of the machine. By not being able to contest the test results, drivers could be penalized and forced to keep the ignition interlock device in their cars for up to another year. That's an extra year per violation. That could also add up to alot of extra fees for extra calibrations. See, http://www.ripoffreport.com/r/Smart-Start-Interlock/nationwide/Smart-Start-Interlock-Smart-Start-is-a-disaster-of-a-company-Nationwide-709179 and http://www.ripoffreport.com/reports/directory/smart-start So it at least appears the company that makes this machine is playing fast and lose with the lives of people.

Ignition interlock devices will only detect the presence of alcohol. https://www.smartstartinc.com/ There are some companies working to develop "breathalyzers" for other substances (i.e. pot); however, it's not currently available commercially.

If your son has a poly-substance abuse problem, taking away his vehicle and getting him some help might be a better idea than an interlock.