254 ARTICLES · UPDATED WEEKLY

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Field guides, regulatory updates, and product breakdowns from the team behind American Screening Corporation's drug testing supplies.

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Page 4 of 22
Benadryl and Drug Tests: Diphenhydramine False Positives Explained

Aug 25, 2026 ·7 min read

Benadryl and Drug Tests: Diphenhydramine False Positives Explained

Diphenhydramine is the active ingredient in Benadryl and dozens of other over the counter allergy pills and sleep aids. It is also one of...

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Nursing Student Drug Testing: What Clinical Placements Require

Aug 20, 2026 ·9 min read

Nursing Student Drug Testing: What Clinical Placements Require

Every nursing student eventually runs into the same wall before their first hospital rotation: a drug screen requirement that has nothing to do with...

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Can Lidocaine or Novocaine Cause a Positive Cocaine Test?

Aug 20, 2026 ·6 min read

Can Lidocaine or Novocaine Cause a Positive Cocaine Test?

A patient gets a filling at the dentist, a minor procedure with a local numbing shot, or a nasal scope at an ENT office,...

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How Long Does Oxycodone Stay in Your System for a Drug Test?

Aug 20, 2026 ·7 min read

How Long Does Oxycodone Stay in Your System for a Drug Test?

Oxycodone is a semi-synthetic opioid sold under brand names like OxyContin, Roxicodone, and in combination products like Percocet. It is a Schedule II controlled...

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How Long Does Fentanyl Stay in Urine? Detection Windows and Cutoffs

Aug 20, 2026 ·7 min read

How Long Does Fentanyl Stay in Urine? Detection Windows and Cutoffs

Fentanyl behaves differently in the body than the opiates a standard drug test was built to catch, and that gap causes real confusion for...

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Prozac and Drug Tests: When Fluoxetine Triggers a False Positive

Aug 20, 2026 ·7 min read

Prozac and Drug Tests: When Fluoxetine Triggers a False Positive

Fluoxetine, sold under the brand name Prozac, is a selective serotonin reuptake inhibitor prescribed for depression, obsessive compulsive disorder, panic disorder, and bulimia nervosa,...

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Cough Medicine and Drug Tests: Why Dextromethorphan Can Read as PCP

Aug 20, 2026 ·7 min read

Cough Medicine and Drug Tests: Why Dextromethorphan Can Read as PCP

A donor takes an over the counter cough suppressant, shows up for a routine urine screen, and gets flagged for phencyclidine. It sounds unlikely,...

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Zoloft and Drug Tests: The Sertraline Benzodiazepine False Positive

Aug 20, 2026 ·8 min read

Zoloft and Drug Tests: The Sertraline Benzodiazepine False Positive

A patient taking sertraline, sold under the brand name Zoloft, can screen positive for benzodiazepines on a standard urine immunoassay without ever having taken...

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What to Expect at a Pre Employment Drug Test

Aug 20, 2026 ·9 min read

What to Expect at a Pre Employment Drug Test

A job offer that comes with a drug test condition follows a fairly predictable sequence almost everywhere in the country. The specifics change depending...

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Wellbutrin and Drug Tests: Why Bupropion Triggers Amphetamine False Positives

Aug 20, 2026 ·7 min read

Wellbutrin and Drug Tests: Why Bupropion Triggers Amphetamine False Positives

Bupropion, sold under brand names including Wellbutrin and Zyban, is one of the most commonly prescribed antidepressants and smoking cessation aids in the United...

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Pseudoephedrine and Meth False Positives: What Confirmation Testing Sorts Out

Aug 20, 2026 ·8 min read

Pseudoephedrine and Meth False Positives: What Confirmation Testing Sorts Out

A urine cup flags amphetamines, and the first thought for a lot of donors is panic over a methamphetamine result they know is wrong....

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Post Accident Drug Testing and the OSHA Rules Employers Get Wrong

Aug 20, 2026 ·9 min read

Post Accident Drug Testing and the OSHA Rules Employers Get Wrong

Most employers believe one of two myths about post accident drug testing. Either OSHA banned it outright, or OSHA has no opinion on it...

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