3 Reasons why phentermine Causes a positive drug test result
Phentermine is a medication prescribed to aid weight loss, and it belongs to the class of amphetamines. Due to its chemical composition, it can show positive results on a drug test for amphetamines. Amphetamines are drugs that stimulate the central nervous system, primarily the brain and spinal cord. These drugs are often prescribed to treat attention deficit hyperactivity disorder (ADHD), narcolepsy (a sleep disorder), and obesity. Amphetamines increase neurotransmitters in the brain, such as dopamine and norepinephrine. This leads to an increase in alertness, attention, and energy. And due to this very reason, these drugs are abused due to the stimulating effects they cause.
Why will Phentermine cause a positive drug test?
Due to its chemical structure, metabolism, dosage, and testing method, Phentermine may cause positive drug test results. Here’s why:
- 1. The chemical structure of Phentermine is similar to amphetamines, which can lead to a false positive result for amphetamines on a drug test. Now, amphetamines are commonly abused for their stimulating effects, which can lead to addiction, tolerance, and other adverse health effects. And when anyone takes Phentermine, their body metabolizes it into amphetamine and methamphetamine byproducts, which can also result in a positive drug test.
- 2. The dosage of Phentermine someone takes determines the likelihood of a positive drug test result. Suppose anyone consumes higher doses or has been using Phentermine for an extended period. In that case, it will increase the levels of amphetamine and methamphetamine byproducts in their system, making it more likely to appear on a drug test.
- 3. The third thing to remember is that the type of drug test used can also impact the likelihood of a positive result. Some tests are more sensitive than others and may detect lower levels of amphetamines or their byproducts, increasing the possibility of a positive outcome.

It is important to remember that having a valid prescription for Phentermine and informing the tester can help account for a false positive result. However, taking Phentermine without a prescription is illegal and can lead to legal consequences.
However, suppose you are taking Phentermine as prescribed by a licensed healthcare provider and have a valid prescription. In that case, you should inform the individual administering the drug test about your medication before taking the test. This way, they can consider that you are taking a prescription medication that may produce a positive result on the test.
On the other hand, taking Phentermine without a prescription or not as prescribed is illegal and can risk your health by extraordinary means. Additionally, suppose you are subjected to a drug test and have Phentermine in your system without a valid prescription. In that case, you may face legal consequences or disciplinary action.
To sum up, Phentermine can cause a positive result on a drug test for amphetamines. However, if you have a valid prescription and inform the tester, it should not be a problem. However, taking Phentermine without a prescription is illegal and can have serious consequences.