Does Phentermine Show Up on a Drug Test?

Many people ask, “does phentermine show up on a drug test?” This is a common question for patients who take phentermine for weight loss or obesity. Phentermine is a stimulant medicine. It can help with appetite control. It is a controlled substance because it works on the central nervous system and brain.

When a patient takes this medicine, they may wonder if it shows up in a urine test, blood test, saliva testing, or even a hair follicle test.

What Is Phentermine?

Phentermine is a medication approved by the Food and Drug Administration for short-term weight loss treatment.

It is often used with a healthy diet, exercise, and sometimes therapy. This medicine works by changing neurotransmitter chemicals in your brain like dopamine, serotonin, and norepinephrine. These brain chemicals affect hunger and mood.

Phentermine is similar to an amphetamine. That is why the Drug Enforcement Administration (DEA) lists it under the Controlled Substances Act.

How Does Phentermine Work in the Body?

Phentermine acts on your nervous system. It helps lower your appetite, so you eat less food. It also speeds up your metabolism and can help with fat loss.

It changes the way your brain sends signals about hunger and concentration. Because it works on your circulatory system, it can raise blood pressure and heart rate.

Can Phentermine Show Up on a Drug Test?

Yes, phentermine can show up on a drug test.

A drug screening looks for signs of drug abuse, addiction, or use of controlled substances. Phentermine can sometimes give a false positive for amphetamine or even methamphetamine on certain tests.

Types of Drug Tests

Urine Test

A urine test is one of the most common. Urinalysis is simple and fast. Phentermine can stay in your urine for 1 to 4 days, depending on the dose and your metabolism.

Blood Test

A blood test may also find phentermine. This type of screening is used less often, but it can detect the drug for up to 24 hours after use.

Saliva Testing

Saliva tests can also detect phentermine. These tests are easy and can show drug use for a short time after taking the medication.

Hair Follicle Test

A hair follicle test looks for long-term use. A small piece of hair is tested. This type of test can show drug use over a period of months.

Why Would You Be Tested?

People are tested for many reasons. Some jobs require drug tests. Some patients are tested by a physician to check for prescription drug addiction or substance abuse.

If you take phentermine, tell your physician, psychiatry team, or insurance provider. This helps explain results.

Risks and Side Effects

Taking phentermine has risk. Side effects can include:

Headache
Nausea, vomiting, or diarrhea
Constipation
Irritability, mood swings, anxiety
Trouble with sleep or insomnia
Palpitations (fast heart beat)
High blood pressure and hypertension
Fatigue

Phentermine can also affect your liver and breathing if misused.

Who Should Avoid Phentermine?

Some people should not use this medication, including those with:

Heart disease or high blood pressure
Pregnancy or breastfeeding
History of addiction or abuse
Mental health issues such as severe anxiety

What About Mixing Phentermine With Alcohol?

Using alcohol while on phentermine is not safe. It may affect your mood, nervous system, and liver. It can also raise your blood pressure and heart rate.

Can Phentermine Be Addictive?

Yes, phentermine can be addictive. It works like amphetamine, so there is a risk for prescription drug addiction or abuse.

Other Drugs That Show Up on a Test

Drug tests may also look for:

Methadone
Opiate
Opioid
Oxycodone
Phencyclidine (PCP)
Adderall
Benzodiazepine
Analgesic pain medicines

How Long Does Phentermine Stay in the Body?

The time phentermine stays in your system depends on:

Your dose
Your metabolism
How often you take it (frequency)
Your diet and healthy diet habits
How much water you drink

Safe Use of Phentermine

Always follow your physician’s directions. Do not take more than your prescribed dose.

Use phentermine with a healthy diet, exercise, and sometimes other medicines like topiramate or semaglutide.

What If You Test Positive?

If you test positive on a drug test, show your prescription. Tell the testing center that you are a patient. A physician may confirm results.

How Does Phentermine Affect Mental Health?

Phentermine can change mood, concentration, and nervous system activity. People with mental health issues like anxiety may need extra therapy and psychiatry support.

Healthy Ways to Lose Weight

Phentermine is not for everyone. Other ways to lose weight include:

Exercise
A healthy diet rich in water and good foods
Therapy for eating habits
Support from a physician or psychiatry professional

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