What could interfer with drug tests?
If you have a history of drug use, you may be asked to submit to drug tests for a court system, a child custody case or an employer.
What if you test positive and you haven't been using?
A false positive drug test reading is possible with urine tests due to foods, prescription or over-the-counter medications already in your system. This is known as cross-reacting. There are several such drugs that have been proven to produce a false positive result. In fact, the Journal of Analytical Toxicology showed error reports of about 10-15% for such drug tests. That’s a pretty big margin of error when the stakes are so high. The error rates are high enough to warrant a good argument for a second test.
At one time, pain relievers which contain ibuprofen, such as Motrin or Advil would cause a false positive for marijuana but this problem has been addressed. Currently, there is no material that will produce a false positive for marijuana. Any medications which contain ephedrine or phenypropanolamine can sometimes test positive for amphetamines, found in products such as Vicks Nasal Spray or Sudafed.
Several types of things can cause a false positive for opiates. Some examples include poppy seeds, the pain reliever Demerol, cough medicines which contain Dextromethorphan and products such as Primatene-M which contains perylamine. A false positive for cocaine can be caused by use of certain antibiotics like amoxicillin and ampicillin. Cold medicines like Nyquil Nighttime can produce a false reading for Methadone.
When filling out the form before your test, consider the substances on the below list. You can note that one or more of these products might be in your system.
Common Substances or Situations leading to falsely positive drug test results:-
Nonsteroidal anti-inflammatory drugs
Vicks Formula 44M
Dristan Nasal Spray
Nyquil Nighttime Cold Medicine
Passive marijuana inhalation.
Pain relievers such as Advil, Nuprin, Motrin and menstrual cramp medications like Midol and Trendar
Amoxicillin - False positives for cocaine
Anti-anxiety pills - Many will test positive for Benzodiazepines
Antibiotics - False positives on Heroin Tests
Asthma medications (Marax, Bronkaid tablets, Primatine Tablets)
Cough medicines - See if any ingredients are on this list
Cough suppressants with Dextromethorphan (DXM)
Diazepam (generic name for valium)
Diazepam False positives for PCP
Dristan Nasal Spray
Elavil - False positives for opiates for up to three days
Ephedra (Ma Haung)
Ephedrine based compounds
Fioricet and derivatives
Ibuprofen - False positives for Marijuana
Lettuce - Both Prickly and Blue
Lortab - an opioid analgesic
Menstrual cramp medications like Midol and Trendar
Most prescription pain medications
Nasal decongestants - False positives for Amphetamines
Nyquil Nighttime Cold Medicine - False positives for Methadone up to 2 days
OTC diet aids with phenylpropanolamine (Dexatrim, Accutrim)
Over-the-counter nasal sprays (Vicks inhaler, Afrin)
Prescription sleeping pills
Primatene-M containing perylamine
Quinine water - False positives for opiates
Robitussin Cold and Flu
Tylenol with codeine
Vicks Formula 44M containing Dextromethorphan
Vicks Nasal Spray
If it truly is a false positive, ask for a second test.