Phentermine Drug Class: Is It A Controlled Substance?

Phentermine is a weight loss drug that possesses a small potential for abuse because of its amphetamine-like qualities. It is considered a controlled substance and has many short-term and long-term side effects.

Is Phentermine A Controlled Substance?

Phentermine is a type of diet pill for helping people who have an unhealthy body weight or body mass index (BMI) to lose weight. It is considered an anorexiant.

Brand names for phentermine include Adipex-P, Ionamin, Lomaira, Suprenza, and Fastin.

Phentermine hydrochloride is sometimes used in combination with another drug called topiramate. A major brand name for this combination of phentermine-topiramate is Qsymia.

Like most prescription weight-loss pills, phentermine is not meant for someone who is looking to lose a few pounds.

This drug is meant for people who are struggling with obesity and for whom other methods of weight loss have not been successful.

Phentermine shares many characteristics with stimulants and is considered a controlled substance by the United States Drug Enforcement Administration (DEA).

It is currently listed as a Schedule IV drug.

Why Phentermine Is A Schedule IV Controlled Substance

A Schedule IV controlled substance is one that is considered to have a low risk for abuse and dependence. Drugs that are listed as Schedule IV also generally possess medical uses and value.

Drugs that are Schedule IV, however, are still considered addictive on some level and can also be dangerous when combined with other drugs or when used alone in high doses.

What Drug Classification Is Phentermine?

Phentermine is part of the drug class called anorectics.

This type of drug has a stimulant effect on the brain and works as an appetite suppressant. Not surprisingly, it is usually found in weight-loss medications.

This type of drug can be dangerous, and it is important to be aware of any drug interactions or contraindications for use, according to the United States Food and Drug Administration (FDA).

Important contraindications to be aware of include:

  • glaucoma
  • history of cardiovascular disease, heart disease, or heart failure
  • hyperthyroidism
  • history of drug abuse
  • recent use of any monoamine oxidase inhibitors (MAOIs)
  • pulmonary hypertension

How Phentermine Works When Ingested

Phentermine helps to suppress a person’s appetite by raising the levels of three of the body’s major neurotransmitters: serotonin, dopamine, and norepinephrine.

As the level of these chemicals rise in the central nervous system, a person’s level of hunger decreases.

Weight-loss medications like phentermine work best alongside other weight-loss methods such as exercise and a reduced-calorie diet.

These lifestyle changes are important, as phentermine is only meant to be taken in the short term.

Short-Term Side Effects Of Phentermine Use

Phentermine has stimulant-like qualities and can produce similar side effects, as it is also known to work the heart and cardiovascular system extra hard.

The following are some common side effects that can occur with phentermine use:

  • constipation
  • dry mouth
  • diarrhea
  • vomiting
  • high blood pressure
  • dizziness
  • chest pain
  • heart palpitations

What Happens When You Abuse Phentermine?

Serious side effects are possible if someone does not follow the instructions of their healthcare provider and abuses phentermine in high concentrations.

Health risks of phentermine abuse include:

  • skin lesions
  • irritability
  • insomnia
  • shortness of breath
  • psychosis
  • psychological dependence
  • heart disease
  • increased risk for heart attack and stroke

Find A Rehab Program For Phentermine Abuse

If you are worried that you or a loved one has become dependent on, tolerant to, or addicted to prescription drugs or substances, please consider giving our helpline a call.

No matter your location or the severity of your addiction, we are here and ready to work with you to help you reach addiction recovery.

This page does not provide medical advice. See more

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