Reasons for a False Positive Drug Test
If you are applying for a new job or play a professional sport, you may be required to take a drug test. You shouldn’t worry if you have not taken illegal substances – but did you know some common medications and foods can cause a false positive? Not all drug tests are perfect, and legal substances can trigger a positive result. Read below to find out reasons for a false positive on a drug screening.
Both prescription and over-the-counter medications have the potential to cause a false positive on your drug test. Some common medications that can result in a false positive:
- Robitussin, Delsym (Dextromethorphan) – Over-the-counter cough suppressants, these medications may cause you to test positive for opiates or PCP (phencyclidine).
- Sudafed (Pseudoephedrine) – A nasal decongestant, Sudafed can cause a false positive for amphetamine or methamphetamine.
- Benadryl (Diphenhydramine) – Common allergy medications, like Benadryl, can cause you to test positive for methadone or PCP.
- Prozac (Fluoxetine) – A depression medication, fluoxetine may show up on a drug test as amphetamine, methamphetamine or LSD.
- Ritalin (Methylphenidate) – Common ADHD medications like Ritalin can cause positive results for amphetamine, methamphetamine and LSD.
- Zoloft (Sertraline) – Some sleep medications, like Zoloft, may result in you testing positive for benzodiazepines or LSD.
Food & Drink
It may seem confusing, but some foods and drinks can cause a false positive when taking a drug test. Poppy seeds and hemp seeds or oils can contain trace amounts of compounds found in opiates and marijuana. While you would have to eat a lot of poppy and hemp seeds to get a false positive, it’s recommended to stay away from these foods if you know you’ll be drug tested.
Tonic water can also cause false positives. Tonic water contains quinine, an organic compound derived from the bark of the cinchona tree. Quinine is similar to in composition to opiates, and it can cause a false positive. Similar to poppy seeds and hemp foods, its best to stay away from tonic water before a scheduled drug test.
Antibiotics are used to fight off bacterial infections, but some can potentially cause a false positive. Rifampin and fluoroquinolones pose the risk of your drug test showing false-positives for opioids. Talk to person overseeing your drug screening and your doctor if you are currently taking these antibiotics to avoid the possibility of a false positive result.
NSAID stands for nonsteroidal anti-inflammatory drugs, which are common household drugs primarily used for pain relief, like ibuprofen. If taken in high doses, NSAIDs can cause a drug test to show up positive for barbiturates (central nervous depressants), benzodiazepines (psychoactive drugs) and marijuana.
Examples of NSAIDs include:
- Motrin (Ibuprofen)
- Advil (Ibuprofen)
- Aleve (Naproxen)
What Do I Do If I Recieve a False Positive
In the event that you find out you have failed a drug test, it’s best to remain calm and remember what you have put in your body. If you have not taken any illegal substances, you can feel confident that the test result is inaccurate. Most companies will allow you to test again, but it’s best to be aware of the medications and foods you are consuming before the test. Always do your research about the potential causes of a false positive to ensure acceptable results.