Can Prescribed Medication Cause You to Fail Drug Test

Taking medicine from your doctor is usually safe and helps with health problems. But, some of these medicines can make you unexpectedly test positive in a drug test because parts of the medicine can look like illegal drugs to the test. This doesn’t happen a lot, but it’s something to remember. 

For instance, out of 100 drug tests, maybe 1 or 2 might show false positive drug tests because of prescription meds. If you have a drug test and you're taking medicine, just tell the people testing you. This way, they won't be confused by the results. Keeping it open and simple can clear up any mix-ups.


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How do Drug Tests work?

Drug tests can sometimes pick up prescription medicines, similar to how they detect illegal drugs. Here’s the deal: when you take any medicine, your body leaves tiny bits of it, like crumbs, in your blood or urine tests. About 50-60% of people in the U.S. take prescription drugs. So, during drug tests, it’s pretty standard to find these bits. 

Tests have a special cut-off level to decide if it's just medicine or something more. If you're taking the medicine your doctor gave you, tell the people doing the test. They check this against the test results to make sure everything matches up and doesn't falsely accuse you of taking illegal drugs.

Why Prescribed Medications Might Cause a Fail

Prescribed medications might cause you to fail a drug test because they contain substances that are chemically similar to those found in illegal drugs. Here’s how it works;

  1. Chemical similarity. Some prescribed medications have ingredients that look almost like illegal drugs to the test.
  2. Detection. Drug tests look for specific drug "signatures" in your body. If your medicine has stuff that matches one of those signatures too closely, the test might flag it.
  3. Threshold levels. Drug tests have limits for what they count as a failed test. Even if your medication's level is low, if it's above that limit, it could count as a failure.

If you're taking medicines your doctor gave you, it’s crucial to:

  • Inform the tester.Let the people testing you know upfront.
  • Provide Documentation. Show proof of your prescription.
  • Follow Up. If necessary, a more detailed test (confirmation test) can be done to show that the results are due to prescribed medication and not illegal drug use.

Common Medications That Could Affect Drug Tests

When undergoing drug testing, it's crucial to be aware that certain common medications can interfere and potentially yield false positive results. As per our research, both prescription and over-the-counter drugs may contain essences or metabolites that are similar to those of the drugs being tested for, so it leads to confusing and concerning outcomes.

  • Suboxone. Buprenorphine, its active ingredient, is tested explicitly for and shouldn't cause false positives for other substances.
  • Metformin. This might lead to false positives for amphetamines.
  • Methylphenidate. It could show up in tests for amphetamines or methamphetamine.
  • Baclofen, Lexapro, and Trazodone. Generally, it shouldn't cause false positives but can interact with other substances or test parameters.
  • Hydroxyzine. It can potentially cause a false positive for certain benzodiazepines or LSD.
  • Amoxicillin. Has been reported to sometimes cause false positives for cocaine.
  • Furosemide. Diuretics that could theoretically alter drug test results but not specifically cause false positives.

Food & Drinks

We are considering food and some drinks too, as most of the time people are stuck into myths vs reality of detox products and drug tests along with Celsius and nicotine, caffeine-based energy drinks. 

  • Celsius Drinks. Shouldn't cause false positives, though their high levels of caffeine and other natural substances might affect some tests.
  • Nicotine. It isn't generally tested for in standard drug-based nicotine urine tests and doesn't cause false positives for other drugs.
  • Dietary Supplements. There are some homeopathic and herbal medications, too, that can become a reason for false positive drug tests. 
  • Herbal Supplements. Certain herbs, like ones found in weight loss pills, might lead to false positives for amphetamines.
  • Biotin. High doses might interfere with some hormone-related tests but are unlikely to affect drug tests.
  • Vitamin C. Unlikely to cause false positives.
  • Vitamin B12. It is not known to cause false positive readings on a drug test.

Also, Can Chemo Cause False Positive Drug Test?

Chemotherapy can sometimes lead to false positives due to the metabolism of different drugs used in treatment.

What the Numbers Say About Prescriptions and Drug Tests

Understanding these factors is crucial in interpreting drug test results accurately, especially when prescriptions are involved.

  • Prescription usage. About 50% of Americans take at least one prescription drug in any given month.
  • False positives. Some everyday meds, like certain antidepressants or antibiotics, might mistakenly show up as illegal substances on drug tests.
  • Impact. This means that in places where drug testing is expected, a large number of people could potentially receive false positive results simply due to their legal medication.
  • Solution. Advanced testing methods help reduce these errors and make sure that prescription drugs don't unfairly impact drug test outcomes.

Tips for Managing Medications and Drug Testing

There is no doubt that medications and drug testing can be tricky, especially if you're taking prescribed medication that could impact your test results. Here are some practical tips to help you manage both seamlessly:

Keep Accurate Records

Always keep detailed records of all your medications, including prescription drugs, over-the-counter medicine, and supplements. A few years back, a survey revealed that about 66% of adults in the U.S. use prescription drugs. So keeping track of your medication not only helps you manage your health but also prepares you for any unexpected drug tests.

Communicate With Your Healthcare Provider

Have a conversation with your healthcare provider before starting any new medication about its potential to affect drug test results. About 45% of Americans have failed a drug test due to legally prescribed medications, according to a study. Your doctor can offer alternatives that are less likely to interfere with drug screenings or provide documentation that you can present in case of a drug test.

Understand Your Rights

If you're taking medication for a health condition, it's important to know your rights. The Americans with Disabilities Act protects individuals who are taking legally prescribed medication for disabilities and assures they are not discriminated against in the workplace. Thus, being aware of these protections can give you confidence and security in your employment.

Be Open With Your Employer or Testing Agency

Well, undergoing any drug test, inform the testing agency or your employer about your prescription use. Approximately 58% of employers conduct drug tests, and being upfront about your medications can prevent misunderstandings. Also, provide them with a list of medications and dosages as prescribed by your doctor.

Request a Confirmation Test if Necessary

If you happen to fail a drug test due to your prescribed medication, you have the right to request a confirmation test. As confirmation tests are more precise and can distinguish between drug abuse and legitimate prescription medication use. This step is crucial for clarifying your situation and protecting your reputation.

Keep Updated on Medication Lists

Medications and their formulations change over time. A drug that didn't cause a false positive a few years ago might do so now due to changes in its composition. 

Also, regularly review the list of substances that could cause a false positive drug test, so this proactive approach can save you from unexpected results.

Steps to Take if You Fail a Drug Test Because of Legitimate Medication

If you've failed a drug test due to your medication, don't panic. Here are some steps to take:

  1. Stay calm and gather your documents. Collect any documents linked to your medication, like prescription slips or a doctor’s note. It's the main thing because the proof is your best friend in these situations.
  2. Inform your employer or test administrator. Let them know right away about your prescription medication. Be honest and direct. According to a recent survey, honesty in such situations is often viewed positively.
  3. Ask for a retest. If your first test didn't go as planned, ask for a second one. Sometimes, the initial test can have errors. A retest can help clear things up.
  4. Provide proof. Hand over any documents that show you're legally taking the medication. This might include prescriptions, letters from your doctor, or pharmacy records.
  5. Consult your doctor. If necessary, talk to your doctor. They can explain to your employer or the testing agency why you need the medication. They might also suggest an alternative that won't affect drug tests.

Around 5-10% of drug tests can result in false positives due to prescribed medications, so it's a common issue and one that can be resolved with the right steps.

Taking these actions will help clear up any misunderstandings and protect your job and reputation.

Real-World Examples to Understand Accounts of False Positives

Even at top labs like LabCorp and Quest Diagnostics, mistakes can happen. If you think there's been a mix-up with your drug test:

  • What to do? Ask them to check again. They have ways to double-check if something doesn't seem right.

For instance, some common medicines can confuse drug tests and make them think there's something else in your system:

  • Prozac. This is a medicine for depression, but sometimes, it might make a drug test think there are drugs like benzodiazepines (a type of calming drug) in your body when there aren't.
  • Risperidone. Used for mental health conditions, it might trick a test into detecting methamphetamine (a strong stimulant) or LSD (a hallucinogen).
  • Omeprazole. This one helps with stomach acid but can surprise you by showing up as methamphetamine or LSD on tests, too.

The Lesson Here?

If you're taking any medicine and need to take a drug test, tell the people testing you. It can help avoid mix-ups and unnecessary stress.

What You Can Do

If you’re taking the medicine your doctor gave you, it might confuse a drug test and make it look like there's something wrong when there isn't. This can happen with medicines for depression, infections, and even heartburn, and this makes the test show drugs that you didn’t actually take. 

If you have to take a drug test, tell the people doing the test about your medicines. If the test says you failed, you can ask for a special retest to prove it was just your medicine. We suggest to always talk about the medication you're taking to avoid mix-ups.

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