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Last night you had what you know was one too many and had to get a cab home. It’s now the next morning, and you’re a bit hungover.

Can you drive?

Will you still fail an interlock test?

Most people assume that after they have slept it off, they are fine. The fact is that, occasionally, you may fail an interlock test the morning after drinking, depending on how much you drink.

Your Ignition Interlock: Morning After Drinking

The answer is: It depends. Alcohol can and will stay on your breath for hours after drinking. Women tend to metabolize alcohol more slowly than men and thus stay drunk longer.

You are more likely to fail a morning after test if you had more than four drinks or if you stayed up very late drinking (which is also a bad idea because you are then likely to be fatigued and thus impaired). So, can you drink the night before interlock tests?

Most people metabolize one unit of alcohol (a pint of beer, a glass of wine, or a shot of spirits) in an hour. But there are a lot of individual variances. If you have a damaged liver, you will also stay drunk longer. Using a portable breathalyzer is an excellent way to help you determine whether alcohol is still in your system and learn how quickly you metabolize it and get it out of your system.

Why Else Might You Fail a “Morning After” Test?

There are a couple of other reasons why you might fail a morning-after breath test:

  1. How long does alcohol stay in your breath? You used excessive alcohol-based mouthwash to deal with post-alcohol dry mouth. Don’t forget that alcohol-based mouthwash can produce a false positive — wait fifteen minutes after using it before trying to drive.
  2. Don’t forget that the limit for your interlock device is often very low, and it may be zero. You may well be sober, but you still have traces of alcohol in your system.

Generally, though, if you fail your ignition interlock test the night after drinking, it means you have not yet metabolized all the alcohol you consumed, and you need to drink less or stop drinking sooner in the evening.

Consider whether you should drink if you are driving the next day. Can you drink the night before interlock tests? While you can drink the night before an interlock test, you should do so responsibly.

How to Pass an Interlock Test While Drinking

Are you wondering, “How to pass interlock when drinking?” The plain answer is you can’t. There is no way to fool the system into thinking you haven’t been drinking, and cheating the interlock could cost you your place in the program and, thus, your ability to drive.

How long does alcohol stay in your breath?

You can’t sober up any faster than your body processes alcohol. If you’re wondering, “how long does alcohol stay in your breath,” you can’t cover it up. Drinking coffee may help you feel better, but it’s only masking your state, not stopping it. Your BAC will continue to stay high. Taking a cold shower is not going to help either, nor is eating a heavier, fattier breakfast. Heavy, fatty food can also cause a false positive, especially with cheaper devices.

Another thing to remember is that being hungover can also impair your ability to drive. A hangover slows your reflexes and can be associated with memory loss. If you are hungover, the best thing to do is take a painkiller, drink a large glass of water, and rest. That’s why you should reserve drinking for nights when you don’t have anywhere in particular to be the next morning.

Can you drink the night before interlock tests?

Failing an interlock test the morning after drinking can happen, if you are not careful enough. The best way to avoid it is not to drink in excess in the first place, drink only when you don’t have work the next day, and to stop drinking earlier in the evening.

In other words, drink responsibly so you don’t have to worry about how to pass interlock when drinking. Also, don’t try to cheat your interlock morning after drinking — it won’t work. To find out more about living on an ignition interlock program and how you can avoid interlock test failures, contact RoadGuard Interlock today.

*Links to any third-party websites herein are provided for your reference and convenience only. RoadGuard Interlock did not create nor develop and does not own any such third-party websites. RoadGuard Interlock does not endorse nor support the content of, nor any opinions stated in any such third-party website links. RoadGuard Interlock is not responsible for the content of any third-party website or its accuracy or reliability. Nothing contained in this article or in any such third-party website shall be considered legal advice or be deemed to constitute legal advice. For any legal advice concerning a DUI arrest, charge, conviction, or consequences thereof, you should contact an attorney of your choice.