PTCB TOP 200 · #168

Phentermine

Adipex-P

Phentermine is the generic name for the brand-name drug Adipex-P. It is an anorexiant (sympathomimetic) used to treat weight loss (short-term). On the PTCE Top 200 drug list, Phentermine ranks #168 and is one of the most frequently tested cns/psych medications — commonly quizzed on its brand–generic pair, drug class, and key side effects.

Generic namePhentermine
Brand name(s)Adipex-P
Drug classAnorexiant (sympathomimetic)
Class groupCNS/Psych
Common useweight loss (short-term)
DEA scheduleC-IV
AvailabilityPrescription only (Rx)

What is Phentermine used for?

Short-term adjunct in a weight reduction regimen based on caloric restriction, exercise, and behavior change for obesity/overweight (product-specific).

What drug class is Phentermine?

Phentermine is an Anorexiant (sympathomimetic) in the CNS/Psych group. Knowing the class is the fastest way to predict its uses, side effects, and the brand↔generic pairs the PTCE tests.

Common side effects of Phentermine

Major interactions

Is Phentermine a controlled substance?

Yes. Phentermine is a C-IV controlled substance under federal law.

How to remember Phentermine (PTCE mnemonic)

ADIPex shrinks ADIPose — phentermine is C-IV sympathomimetic appetite suppressant. ↑BP/HR, insomnia, dry mouth; ≤12 weeks; NO MAOIs/SSRIs (HTN crisis), NO cardiac dz.
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PTCE exam tip

Phentermine is a C-IV appetite suppressant for SHORT-term use — its stimulant nature explains the scheduling, and it also appears inside Qsymia with topiramate.

Phentermine FAQ

What is the brand name for Phentermine?

The brand name for Phentermine is Adipex-P.

What is Phentermine used for?

Phentermine is used to treat weight loss (short-term). Short-term adjunct in a weight reduction regimen based on caloric restriction, exercise, and behavior change for obesity/overweight (product-specific).

What drug class is Phentermine?

Phentermine is an Anorexiant (sympathomimetic) (CNS/Psych group).

Is Phentermine a controlled substance?

Yes. Phentermine is a C-IV controlled substance under federal law.

Study guides that cover Phentermine

Free, in-depth guides to the patterns behind this drug — no app needed.

See all PTCE study guides or browse the full Top 200 drug list.

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Related drugs in the CNS/Psych group

Written and reviewed by the RxReflex Content Team. Educational use only — not medical advice. Verify clinical specifics with your pharmacist or a current label source such as DailyMed. RxReflex is not affiliated with or endorsed by the Pharmacy Technician Certification Board (PTCB).