Australia Drug Testing


By Australia Drug Testing / November 10, 2023

By Australia Drug Testing / November 10, 2023

Can food and drinks Give False Positive drug test?

positive drug test - Australia Drug Testing

A common household item hanging around the kitchen that seems innocent could be the reason why your employee’s test result is a positive drug test. This false positive result can be caused by certain meals, beverages, and prescription drugs having drug related compounds and metabolites in them.

Food and Drinks That Can Trigger False Positive Drug Test Results

1. Pizza

Pizza is typically thought of as the pinnacle of culinary skill. It is an admired and cherished dish, cutting across all cultural barriers.

However, consuming a slice of pizza could result in a false positive on a breathalyser drug test. How so? The dough for your pizza or any other pastry rises because yeast encourages the fermentation of glucose into alcohol and other chemicals.

A slice of pizza shouldn’t make you feel drunk, but the alcohol in it could be just enough to cause a false positive on an alcohol test. So if your employee recently had pizza before a drug test, it may lead to a false positive result.

2. Poppy Seeds

If your employee starts their day with a poppy seed bagel, it might be advisable to break the habit if they have a drug analysis test coming up.

One of the meals that result in a false-positive drug test is these little black seeds. Some organisations expressly forbid consuming poppy seeds before a drug test procedure, and here’s why:

The opium poppy used to create heroin is derived from the small crunchy seeds that people sprinkle on cakes, cookies, and bagels. Despite being safe, the seeds contain minute levels of morphine and codeine, around 0.5-10 micrograms per gram.

Especially when you consider that morphine given for medical purposes has a concentration of 5,000–30,000 micrograms/gram, this opiate concentration is far from anything that might make you feel high.

A drug test procedure, however, may fail to distinguish between poppy seeds and other stronger, illegal opiates. The World Anti-Doping Agency code suggests 1.3 micrograms per gram morphine threshold. Additionally, consuming poppy seeds raises the possibility of a false positive drug test, according to a study published in the Journal of Analytical Toxicology.

3. Durian Can Trigger a Positive Drug Test

Few, if any, fruits are as contentious as the durian. The Asian fruit is simultaneously revered and despised. Some people love it as a snack because of its high nutritional content, distinctive flavour, and custardy texture. Others find the strong aroma it releases when ripe intolerable.

The prickly Asian fruit is one of the foods that may result in a false positive breathalyser alcohol test. This is because of the lingering mouth alcohol which occurs after eating a durian fruit. 

4. Hemp Seeds

drug testing hemp seed - Australia Drug Testing

Hemp seeds are a variety of the Cannabis sativa L. plant. However, it has less than 0.3% of the psychoactive ingredient in marijuana, known as THC.

People recognise hemp and hemp seeds as controlled goods. As a result, there is a considerable likelihood that you’ll consume hemp seeds or items containing hemp oil, such as granola bars.

Hemp contains just minute levels of THC (tetrahydrocannabinol), about 0.3%, which is insufficient to make a person feel high. Still, the psychoactive component may build up in your fat cells and persist for up to 5 weeks. Therefore, your employee can fail a drug test without doing drugs if they regularly ingest hemp seeds.

5. A Cup of Coca Tea

Wondering how your employee can test positive for drugs without using them? Drink some coca tea right before taking a drug test. Coca tea is a tasty beverage made from coca leaf, the same plant as cocaine.

Based on a study, coca tea breaks down to produce cocaine metabolites, which may lead to a false positive. The research found traces of the metabolites in the body for up to 36 hours. And they could detect the substance in as little as 2 hours.

6. Tonic Water Can Cause a Positive Drug Test

Here’s an additional drug testing fact: tonic water is another beverage that may result in a false positive drug test. Tonic water was initially advertised and consumed for its quinine content, an ingredient that could treat malaria.

In more recent times, quinine is frequently used to trim illegal substances like heroin. This is why consuming a bottle of tonic water may cause your urine to indicate drug use. The connection between quinine and street drugs may result in a false positive urine drug test.

What Should an Employee Not Take Before a Drug Test?

Food and beverages are just some of the things that might cause a drug analysis test to fail. Another reason your employee might fail a drug test is if they consume illicit substances. You can also receive a false positive result because of some over-the-counter medications such as:

  • Acetaminophen
  • Alcohol
  • Antihistamines
  • Aspirin
  • Caffeine
  • Vitamin B

How Can You Reduce the Risk of False Positives

Educate your employees on the foods and drinks to avoid before taking a drug test. 

Since foods, drinks, and certain prescription medications can trigger a false positive in an indicator test, it is recommended that samples of a positive result are sent to an approved laboratory for further analysis and confirmation.

Alcohol from foods hardly enters the system; hence, a blood test or further laboratory examination can help reveal a false positive. Also, you can detect a wide range of drugs with advanced tests like High-Performance Liquid Chromatography (HPLC) or Gas Chromatography-Mass Spectrometry (GC-MS). These tests separate and mark the components in your urine sample to look for potential interference.

You should handle indicator test results discreetly until you have completed the lab test. The last thing you want is openly accusing an employee of drug abuse and then finding out later that it was only a case of poppy seeds, which they had consumed.

You should explicitly capture in your workplace drug and alcohol policy what happens if a drug test returns positive. And your employees should be knowledgeable of the procedure. 


Foods that trigger false positive drug tests may have no bearing on the results. The result might accurately indicate a drug and alcohol issue that requires help from professionals. Learn more on how to choose and use drug tests.

Ultimately, there are a lot of things to consider when conducting a drug test. You should inform your staff of what may produce a false positive result. They should be conscious of the food and drugs they consume before the test. In the event that a medication triggered the false positive, a pharmacist or doctor may provide written evidence to support this, if that’s what you have stated in your drug policy.