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Details

Stereochemistry ACHIRAL
Molecular Formula C10H15N
Molecular Weight 149.2328
Optical Activity NONE
Defined Stereocenters 0 / 0
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of PHENTERMINE

SMILES

CC(C)(N)CC1=CC=CC=C1

InChI

InChIKey=DHHVAGZRUROJKS-UHFFFAOYSA-N
InChI=1S/C10H15N/c1-10(2,11)8-9-6-4-3-5-7-9/h3-7H,8,11H2,1-2H3

HIDE SMILES / InChI

Molecular Formula C10H15N
Molecular Weight 149.2328
Charge 0
Count
MOL RATIO 1 MOL RATIO (average)
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

Description

Phentermine is an amphetamine that stimulates neurons to release or maintain high levels of a particular group of neurotransmitters known as catecholamines; these include dopamine and norepinephrine. High levels of these catecholamines tend to suppress hunger signals and appetite. The drug seems to inhibit reuptake of noradrenaline, dopamine, and seratonin through inhibition or reversal of the reuptake transporters. It may also inhibit MAO enzymes leaving more neurotransmitter available at the synapse. Phentermine (through catecholamine elevation) may also indirectly affect leptin levels in the brain. It is theorized that phentermine can raise levels of leptin which signal satiety. It is also theorized that increased levels of the catecholamines are partially responsible for halting another chemical messenger known as neuropeptide Y. This peptide initiates eating, decreases energy expenditure, and increases fat storage. Phentermine is indicated in the management of exogenous obesity as a short term (a few weeks) adjunct in a regimen of weight reduction based on caloric restriction. Phentermine hydrochloride is a sympathomimetic amine with pharmacologic activity similar to the prototype drugs of this class used in obesity, the amphetamines. Actions include central nervous system stimulation and elevation of blood pressure. Tachyphylaxis and tolerance have been demonstrated with all drugs of this class in which these phenomena have been looked for.

CNS Activity

Originator

Approval Year

Targets

Primary TargetPharmacologyConditionPotency
0.31 µM [EC50]
498.0 µM [Ki]
375.0 µM [Ki]

Conditions

ConditionModalityTargetsHighest PhaseProduct
Primary
ADIPEX-P

Cmax

ValueDoseCo-administeredAnalytePopulation
44.78 ng/mL
7.5 mg single, oral
PHENTERMINE plasma
Homo sapiens
49.1 ng/mL
15 mg single, oral
PHENTERMINE plasma
Homo sapiens

AUC

ValueDoseCo-administeredAnalytePopulation
2057.33 ng × h/mL
7.5 mg single, oral
PHENTERMINE plasma
Homo sapiens
2000 ng × h/mL
15 mg single, oral
PHENTERMINE plasma
Homo sapiens

T1/2

ValueDoseCo-administeredAnalytePopulation
20.63 h
7.5 mg single, oral
PHENTERMINE plasma
Homo sapiens
20 h
15 mg single, oral
PHENTERMINE plasma
Homo sapiens

Funbound

ValueDoseCo-administeredAnalytePopulation
82.5%
15 mg single, oral
PHENTERMINE plasma
Homo sapiens

Doses

AEs

OverviewOther

Other InhibitorOther SubstrateOther Inducer



Drug as perpetrator​

Drug as victim

PubMed

Sample Use Guides

In Vivo Use Guide
Usual Adult Dose for Weight Loss 15 to 37.5 mg orally once a day before breakfast or 1 to 2 hours after breakfast. Usual Pediatric Dose for Weight Loss 17 years or older: 15 to 37.5 mg orally once a day before breakfast or 1 to 2 hours after breakfast.
Route of Administration: Oral
In Vitro Use Guide
Phentermine inhibited serotonin-metabolizing (MAO-A) activity in rat lung, brain, and liver with K(i) values of 85-88 uM.
Substance Class Chemical
Record UNII
C045TQL4WP
Record Status Validated (UNII)
Record Version