Phentermine
Metabolic Health · Sympathomimetic
Also known as: Adipex-P ·Lomaira
Tier B-
Bottom line
Read Off Label grades Phentermine as B- (6.0/10) based on strong evidence, med-high benefit magnitude, and a med-high-risk safety profile.
Oldest weight loss drug still on market (1959).
Typical use: 15-37. — Rx.
What this is
Oldest weight loss drug still on market (1959). Pulled from combination (fen-phen) after valvular heart disease reports in 1997. Modern use typically short-term and with cardiovascular monitoring.
Mechanism
Amphetamine-derivative; stimulates norepinephrine release in hypothalamus; appetite suppression via catecholaminergic signaling
Dose & route
15-37.5 mg PO daily morning; intended for short-term (12 week) use
Citations
- https://pubmed.ncbi.nlm.nih.gov/30932373/
- https://www.ncbi.nlm.nih.gov/books/NBK574573/
- https://pubmed.ncbi.nlm.nih.gov/12119565/
- https://clinicaltrials.gov/study/NCT00000506
- https://doi.org/10.64030/2573-8895.04.01.04
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Common questions
- Does Phentermine work?
- Read Off Label rates the evidence for Phentermine as Strong and the benefit magnitude as med-high, producing an overall grade of B- (6.0/10). Oldest weight loss drug still on market (1959).
- Is Phentermine safe?
- Phentermine has a med-high risk profile in published human data. Legal status: Rx (Schedule IV). This is not medical advice — see the disclaimer.
- What is the typical dose for Phentermine?
- 15-37.5 mg PO daily morning; intended for short-term (12 week) use
- How does Phentermine work?
- Amphetamine-derivative; stimulates norepinephrine release in hypothalamus; appetite suppression via catecholaminergic signaling
This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.