With many employers making use of random drug testing in the work place, employees sometimes wonder about the possibility of registering a false positive on a drug test. The fact is there are a number of different over the counter medications, foods, vitamin supplements and even prescription medicines that can cause a false positive on a drug test. Here are some examples.

Among over the counter medicines, many of the night-time cold medications people use to minimize cold and flu symptoms for the evening can cause false positives. This is particularly true of the liquid cold relievers, as many of them contain various members of the ephedrine family. Some of the weight loss products also can result in registering a false positive when testing for drugs is conducted. Even some nasal sprays and over the counter asthma products can create a false positive on a drug test.

Foods can sometimes bring back a false positive on a drug test. Many people are familiar with the fact that poppy seeds can throw off the results on drug tests by showing up as an opiate. Poppy seeds are often used in salad dressings, as an ingredient in many casseroles, and as an added topping on buns and rolls.

Vitamin supplements can sometimes lead to a false positive on a drug test. Riboflavin, also known as B2 can return a false THC reading. Along with being part of most B complex vitamin supplements, the riboflavin is found in hempseed oil and also as a stand alone supplement. Many herbs that contain moderate to high amounts of B vitamins may also bring back a false positive when testing for drugs is taking place.

Prescription medications can also register a false positive on a drug test. Antibiotics like ampicillin and amoxicillin are prime examples. A number of prescription pain medications may return a false positive. Even some anti-anxiety medications will show up as an indicator of one type of illegal drug or another.

Some diseases can also lead to a false positive on a drug test. Conditions such as diabetes, liver disease, and kidney infections may register as opiates on drug tests. When preparing for a drug test, it is a good idea to provide a list of any medications taken recently, as well as vitamins and any herbal supplements. If the individual undergoing the drug test has an ongoing medical condition, that information should be provided also. This can make a huge difference in evaluating the final results of the drug test.