How Long Does Phentermine Stay In Your System?

  How long does phentermine stay in your system? In the USA, one of the most prescribed drugs is phentermine. Its primary function is to suppress appetite in obese individuals to help them cut weight. Generally, this diet pill is like amphetamine and was first–FDA approved back in 1959 for short-term obesity management.

how long does phentermine last

Since this diet pill has amphetamine properties, it might be mistaken that you’re on drugs; suppose the drug test turns positive. Suppose you’re eyeing a particular job and a drug test is a must, then you might be wondering how long Phentermine stays in your system for a minimum of 2 days.

What is Phentermine?

Before jumping How many hours does phentermine last? it’s crucial to know what it is and how it works. As previously mentioned, phentermine is a prescription diet pill for obese people.

Phentermine weight supplement was designed for a short-term usage lasting 12 weeks for persons over 16 years of age. Back in the 90s, drug makers combined this drug with the other two—dexfenfluramine and fenfluramine. The combination was commonly identified as fen-phen.

When reports of heart problems among some users began skyrocketing, the FDA decided to pull the other two weight loss treatment medications from the market.

Nowadays, phentermine is mainly used as a standalone weight loss drug under the brand names; Adipex–P, Suprenza, and Lomaira.[Check out: PhenGold Reviews: Safe Weight Loss Pill For Consumers Or Not?]

However, other weight loss supplements like Qsymia contain Phentermine and topiramate. So, as long as you have a prescription, you can easily get your hands on this drug. Additionally, it has a risk of dependency, that’s why it’s a controlled substance in the USA.

As you already know, chemically, phentermine is similar to amphetamine, another controlled substance. Only if you’re obese is when a health professional can prescribe this pill. Plus, your body mass index BMI must be greater than 30 to be considered obese.

Also, in a case where your BMI is 27 or higher and you have a weight-related condition like high blood pressure, your doctor may prescribe this drug for you.

How does Phentermine Work?

As an appetite suppressant, Phentermine falls under drugs known as anorectics(1). Using this pill equals fewer calories consumed—courtesy of its appetite suppressant property which limits the consumption of excess calories.

This leads to gradual loss of body weight. However, it’s not clear how phentermine works to reduce appetite.

Some researchers, though, think the drug suppresses appetite by increasing levels of neurotransmitters in the brain. These neurotransmitters are the body’s messengers, and they include; norepinephrine, dopamine, and serotonin.

If there’s a spike in these three chemicals’ levels, your appetite will reduce. But, you will likely develop appetite-suppressing tolerance to these pills over a few weeks. Suppose you notice this, then seek professional advice from the health care provider who prescribed it.

How long for phentermine to leave your system Or Your Blood?

Regardless of the dosage, you’ve taken, this drug’s time frame is determined by its profile, known as the half-life(2). The term “half-life ” is the amount of time your body takes to metabolize 50% of the drug, which means that 50% of the drug reduces in every half-life.

how long can i take phentermine

Besides the half-life, which indicates how long a drug can remain detectable in your system, other factors influencing this time frame include;

  • Duration of drug usage
  • the type of test
  • Presence of detectable metabolites

So remember, the half-life is just one aspect.

Phentermine, on the other hand, has been found to have 5-6 half-lives on a standard urinalysis test. Within the body, phentermine has a half-life of between 19 and 24 hours.

According to this, the approximate duration through which this drug will remain detectable is 5 to 6 days. Generally, Phentermine is orally administered, and whether you decide to ingest it in your food or on an empty stomach, none of these aspects will affect the drug’s property.

Primarily, it’s the kidneys that excrete the drug. That’s why the drug is capable of altering your urine’s PH. And as previously mentioned, a single half-life can take between 19 and 24 hours.

But an acidic environment reduces the half-life duration to about 7-8 hours. After ingesting phentermine, most absorption will occur within the small intestines. It takes the body 12 to 14 hours to absorb 30-37.5 mg of Phentermine capsules and 4 hours for the 8mg tablet.

What will a Drug Test be Looking for?

Nowadays, drug tests are among the top factors to consider when hiring an individual to see if they are using drugs and whether or not they’re the right people for the job.

Drug tests are geared toward providing a safe environment for employees. Also, workplace drug tests aim to discourage other employees who may potentially use drugs from using. Moreover, drug tests are held to identify and help individuals at the workplace struggling with drug dependency cope well.

The most common type of drug test is Urinalysis. This method is most effective in identifying top abused drugs such as cocaine, amphetamine, opiates, PCP, and THC.

Suppose your initial and confirmation test results are both positive, then the medical review officer will contact you to verify that the results aren’t for any medical reasons. It’s only at this point that the MRO can report to the employer the results.

Some medications can also show false-positive results on the test. In such a situation, you’re at liberty to verify that you’re under a prescribed medication and that you’re taking your medicine accordingly. That way, the MRO will report the test as negative. Finally, as Mark Brown once put it, “many players won’t be willing to take the drug test after realizing there’s no need to study for it.”

Final Thoughts

While the phentermine drug might be an effective standalone appetite suppressant and weight loss supplement, a combination with topiramate makes it even more effective for long-term use. As a standalone supplement, phentermine is prescribed for short-term use only.

Notably, the combined version can help reduce binging in BED people. Though an effective weight loss supplement, phentermine isn’t suitable for first-line treatment. As Katy Ladere once said, “thinking of myriad ways of dying is thinking of different ways we die, delinquent on our brains in debt. If we settle the de

Frequently Ask Questions:

How long does Adipex stay in your system?

When you take Adipex, it takes about Twenty (20 hours) for half of the dosage to be metabolized by the liver or excreted in the urine.

If you are taking Adipex, your body may require up to six half-lives before your body has time to eliminate the drug completely.

How to flush phentermine out of your system?

The right way to stop Adipex use is to taper it slowly. The effects of Adipex typically wear off in two days. After that, the drug no longer works.

Phentermine helps you feel fuller longer and burn fat more easily. If you are taking or have taken Adipex in the past or are currently taking it, and planning to take a test, you need to tell the tester.

Does phentermine show up on a 10-panel drug test?

Taking Phentermine may sometimes show up as a false-positive urine test for amphetamines. You might need to let the tester know the truth.

Jennifer Singleton is a registered nutritionist and fitness writer who is passionate about fitness nutrition and accomplishing better health by spending time between the gym and the kitchen. Jennifer completed her undergraduate degree at the Ohio State University. You can learn more on her by By Visiting here. Her LinkedIn Page  Or Follow her on Twitter.
Jennifer Singleton
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