Phentermine is a prescription drug used to treat obesity. Service Members often ask about phentermine and other anti-obesity medications to help them lose weight and improve their health and performance. But, policies regarding the use of these drugs continue to change. Currently, several military working groups are preparing updated guidance on the use of anti-obesity medications.

Can military doctors prescribe phentermine and other prescription medications for weight loss?

TRICARE covers anti-obesity medications if individuals meet the prior authorization (PA) criteria. Currently, service-specific and duty-specific policies are under review since outdated policies conflict with newer guidance have proven confusing for healthcare providers and Service Members.

According to the Defense Health Agency (DHA) Pharmacy Operations Division’s MTF Formulary Management for Weight Loss Agents, “All new and current users of weight loss agents (including the generic drugs and branded products) must complete a manual PA. For all the products, lifestyle intervention is required for 6 months prior to starting therapy, and must be continued throughout therapy.” Specific medications may have additional requirements. For full manual PA criteria for phentermine and other anti-obesity drugs, please use the TRICARE Formulary Search Tool.

The use of anti-obesity medications during training, deployments, or operational platforms might not be authorized. However, these medications might be allowed on a case-by-case basis, depending on service-specific policies and provider recommendations. Service Members should discuss potential operational, training, and deployment impacts with their Department of Defense (DoD) medical officer before starting these medications.

Can civilian doctors prescribe weight-loss medications to Service Members?

Civilian doctors who evaluate and treat Service Members for obesity may prescribe anti-obesity medications but should be familiar with the TRICARE coverage algorithm.

Service Members should use their installation’s Medical Treatment Facility (MTF) providers whenever possible. These providers will be more knowledgeable about service-specific policies regarding medications for weight loss, as well as any local controls that might exist. In the long run, using MTF providers could help prevent problems with going against policy.

Phentermine and drug testing

Service Members should ensure all their medications are recorded in their military health record and work with their military Primary Care Provider to ensure their record is updated to reflect any missing prescription medications. Because phentermine is similar to amphetamine, it might register on an initial urine screening test for amphetamines. If this happens, the specimen goes through another analysis for confirmation. Phentermine will not cause a positive result on the confirmation drug test or be reported as positive through the military drug-testing program.

Many prescribed and over-the-counter medications and supplements have become popular weight-loss tools through news reports and social media. Below are some additional articles about sought-after weight-loss substances.

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Updated 19 January 2024