The following list describes, on average, how long certain drugs tend to stay in a person’s body after the last dosage, determining the period of time that they can be detected by urine tests. It can take anywhere from a few hours to a few weeks for the body to rid itself of toxins depending upon the weight and chemical composition of a person. It’s possible for substances, foods and physical ailments to produce false positives in a urinalysis, information that is also included in the list below. In case you are anticipating a drug test, it’s wise to avoid those substances that could potentially yield a negative outcome, although most false positives can be ruled out by confirmatory testing.
Amphetamine: Up to 30 hours on low dose; 5 days on high dose
Possible false positives: Decongestants, like Sudafed; some varieties of OTC and prescription diet pills, like Dexatrim; the antidepressant Zoloft
Barbituates: 7 days for long-acting; 2-3 days for intermediate-acting; 1-2 days for short-acting
Possible false positives: None
Methadone: 7.5-56 hours
Possible false positives: Unisom Nighttime Sleep Aid
Heroin: 1-4 days
Possible false positives: Some antibiotics, like Cipro; cold remedies with dextromethorphan; poppy seeds produce a true positive test because they are the natural source of opiate drugs
Valium: 2-4 days for low dose (although very small doses may not be detected at all); 3-7 days for higher dose.
Possible false positives: None
Marijuana: 7-34 days for once weekly use; Up to 81 days for heavy daily use
Possible false positives: Hemp; Ibuprofen; controversy is stirring over the possibility that second hand inhalation can produce false positives
Cocaine: 8-48 hours
Possible false positives: Tonic water; diabetes
Quaalude: Up to 90 hours
Possible false positives: None
PCP: 5-10 days
Possible false positives: Thioridazine, an antipsychotic drug
Alcohol: Arguably 8-10 hours
Possible false positives: None
As always it is better to be drug free - if you or a loved one need addiction treatment give us a call.
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This is very interesting. I think some thing that drugs leave your system quickly. It is especially interesting that marijuana stays in your blood for so long, especially if you are a heavy drug user. Passing a drug test to get a job is more common than ever, and it’s unfortunate to think that you might not have a successful career, in addition to the many other complications, if you use drugs. Thanks for sharing.
I think drug testing is a complete joke. Many people take B12 and drink alot of water to pass a urinalysis. What i do in the privacy of my own home is not my employers bussiness or anyone elses for that matter. Weed has been on this planet for 1000s of years and people have been smoking it since we figured out we could. I’m not going to say that you should be able to smoke weed whenever you want or that its appropiate all the time but if a substance makes life more enjoyable then why not???
Hey I don’t think that marijuana affects your performance at work. I am a daily toker and I never have any problem evolving my job. Besides, on the past December I was selected as the employee of the month.