Phentermine: Benefits, Risks And Drug Test Effects!

Phentermine: Benefits, Risks And Drug Test Effects!


Phentermine is an amphetamine-like substance that is used for suppressing appetite. It was first approved by the FDA in 1959 for use in the short-term management of obesity. Since phentermine is similar to AMP/amphetamine in many ways, you can get yourself tested for AMP before your pre-employment drug test.

A simple 12 panel urine drug test kit can detect AMP and has a detection window of  up to 7 days while a hair follicle drug test kit can detect up to 90 days. Keep in mind that standard 5 panel and 10 panel urine drug tests do not detect AMP. This does not apply to saliva, hair or nail drug tests. 

Phentermine helps lose weight by decreasing appetite while making you feel energetic and boosted. In 2012, it was approved to be used in combination with topiramate (an anticonvulsant), which produced the same desired weight loss while significantly decreasing phentermine dosage.

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Phentermine is a Schedule IV drug and belongs to a class of drugs called sympathomimetic amines. Long-term use of sympathomimetic drugs such as phentermine has a potential for abuse. Phentermine side effects include dry mouth, dizziness, constipation, insomnia, tingling or prickling sensation, increased heart rate, and fatigue.

Does Phentermine show up on a drug test?

Phentermine has a chemical structure similar to amphetamine and can show up on a drug test that screens for amphetamine. A urine drug test is the most prevalent method for screening illicit substances in workplace drug testing. A standard urinalysis typically screens for MMJ, opiates, phencyclidine (PCP), cocaine, and amphetamines.

Can Phentermine get you high?

Like many prescription medicines such as opioids, phentermine can create a high, especially taken in large doses. Snorting, smoking, and mixing with alcohol are popular ways in which phentermine is abused.

Using phentermine in ways other than prescribed by your healthcare provider can put you at high risk of addiction, tissue damage in the lungs and esophagus, and cardiovascular complications.

How long does Phentermine stay in the system?

The duration for which a drug lasts in the system depends on several factors such as heredity, the rate of metabolism, the quantity consumed, the quality of the substance, hydration, and, importantly, the frequency of drug use.

Phentermine has a half-life of about 16-31 hours. It can be detectable in the urine for 1-3 days. However, heavy and long-term use of phentermine may result in having much longer detection windows.

Phentermine vs. Amphetamine

Phentermine is related chemically to amphetamine. Both phentermine and amphetamine stimulate the central nervous system and induce the same adrenergic receptors in the brain.

The most crucial difference between phentermine and amphetamine is in the amount of dopamine released. The release of dopamine is much higher in amphetamine in comparison to phentermine which makes it highly addictive.

Does Phentermine cause a false positive drug test?

Phentermine can give a false positive in a drug test. Because of its structural characteristics that closely resemble amphetamine, most panel drug tests will detect phentermine and give a positive result.

If you know that you will be drug tested, it is essential to inform your direct supervisor, employer, or the medical review officer (MRO) prior to the testing. In such cases, a false positive will be treated as a negative.

Does Phentermine give you energy?

Phentermine stimulates the secretion of noradrenaline in the brain, and noradrenaline, in turn, suppresses appetite by stimulating adrenergic receptors. It also stimulates the release of dopamine and adrenalin that increases energy and alertness in the body.

Does Phentermine help you burn fat and lose weight?

Phentermine increases energy in the body while reducing appetite and minimizing craving for food. To get satisfactory results, combining with an exercise plan and introducing healthy diet regimes is recommended.

Does Phentermine cause hair loss?

Long-term phentermine use, in some instances, may lead to hair loss. Most phentermine users may experience hair loss around three months into their treatment. Some studies point to the relationship between loss of visible hair and amphetamine.

Not much is known about the exact cause of hair loss among phentermine users.  It is thought to be an effect of increased calorie restriction and elimination in the body. Hair loss among phentermine users may last as long as the medication is taken for treating weight loss.

The bottom line

Phentermine is one of the most popular weight loss medications available in the United States.  It helps suppress appetite and boost energy. This being said, it should be combined with a healthy exercise and diet regimen. Additionally, you have to be careful not to use phentermine for body toning as it is a prescription medicine for the management of obesity and carries serious side effects.

This amphetamine-like substance can potentially cause a wide range of complications such as fatigue, dry mouth, dizziness, constipation, insomnia, tingling or prickling sensation, and increased heart rate. Some users may also experience withdrawal symptoms during the medication. Because of its structural characteristics that closely resemble amphetamine, most panel drug tests will detect phentermine and give a false positive result. For this reason it is important to stick to the prescription and not go overboard with its use.

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