What is the brand name for Phentermine?
The brand name for Phentermine is Adipex-P.
PTCE 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 name | Phentermine |
|---|---|
| Brand name(s) | Adipex-P |
| Drug class | Anorexiant (sympathomimetic) |
| Class group | CNS/Psych |
| Common use | weight loss (short-term) |
| DEA schedule | C-IV |
| Availability | Prescription 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
- arrow_rightInsomnia
- arrow_rightDry mouth
- arrow_rightIncreased heart rate
- arrow_rightElevated blood pressure
- arrow_rightNervousness
- arrow_rightRestlessness
- arrow_rightIrritability
- arrow_rightConstipation
- arrow_rightHeadache
Major interactions
- arrow_rightMAO inhibitors (contraindicated; hypertensive crisis risk)
- arrow_rightOther sympathomimetics/stimulants (additive cardiovascular/CNS stimulation)
- arrow_rightSerotonergic antidepressants (SSRIs/SNRIs) and other weight-loss drugs (risk of serotonin syndrome or additive effects)
- arrow_rightAlcohol may worsen CNS effects
- arrow_rightAntihypertensives: may reduce BP control (monitor)
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.
lightbulb
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 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.
Related drugs in the CNS/Psych group
Drill Phentermine the way the PTCE asks it
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Last reviewed June 25, 2026. 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).