Last updated: March 2026
How Much Does Phentermine (Adipex-P) Cost?
Cost Breakdown by Type
| Type / Procedure | Without Insurance | With Insurance |
|---|---|---|
| Phentermine 37.5mg Tablet | $10 – $25 | $5 – $15 |
| Phentermine 15mg Capsule | $10 – $20 | $5 – $12 |
| Phentermine 37.5mg Capsule | $12 – $40 | $5 – $20 |
What Affects the Cost
- Brand-name vs. generic availability
- Insurance formulary tier placement
- Pharmacy choice (retail vs. mail-order vs. Costco)
- Manufacturer savings cards and coupons
- Dosage and quantity prescribed
- Geographic location
Insurance Coverage
Typical coverage: Tier 2 generic — limited coverage; many plans exclude weight loss medications; 3-month max typical
Most insurance plans use a tiered formulary: Tier 1 (generic) $0-$15 copay, Tier 2 (preferred brand) $25-$75, Tier 3 (non-preferred brand) $50-$150, Tier 4 (specialty) $100-$500+. Prior authorization may be required for certain medications. Step therapy may require trying cheaper alternatives first.
How to Save Money
- Always ask for generic when available — saves 50-90%
- Use GoodRx, RxSaver, or similar discount cards
- Costco pharmacy is open to non-members and often has lowest prices
- Mark Cuban's Cost Plus Drugs offers transparent low pricing
- Manufacturer patient assistance programs provide free medication to qualifying patients
- HSA/FSA funds can cover medication costs tax-free
Related Procedures & Costs
Frequently Asked Questions
Generic phentermine costs $10 to $40 per month without insurance. It is the most affordable prescription weight loss medication available.
Coverage varies widely — many insurance plans exclude weight loss medications. Some plans cover phentermine for a limited period (typically 3 months) with documented medical necessity.
Phentermine is FDA-approved for short-term use (up to 12 weeks). Some doctors prescribe it longer off-label, but it is a Schedule IV controlled substance with potential for dependence.