Drug Coverage

TRICARE covers most prescription drugs approved by the U.S. Food and Drug Administration. The TRICARE Formulary is a list of generic and brand-name prescription drugs TRICARE covers. Check the formulary for coverage information for specific drugs.

Prescription drugs may be covered under the TRICARE pharmacy benefit or the medical benefit.

Prior Authorization, Medical Necessity, and Step Therapy

Prior Authorization and Medical Necessity

Prior authorization is a routine process. We use it to make sure your prescription drug is safe, effective, medically necessary, and cost-effective.

You may need prior authorization for your prescription if it:

  • Is specified by the DOD Pharmacy & Therapeutics Committee
  • Is a brand-name prescription drug with a generic substitute
  • Has age limits
  • Is prescribed for an amount more than the normal limit

Medical necessity is a determination that a non-formulary drug is reasonable for the treatment of a certain medical condition.

You can check the TRICARE Formulary to see if your drug has prior authorization or medical necessity requirements.

How To Get Prior Authorization or Medical Necessity

  • Search for your drug on the TRICARE Formulary.
  • Download and print the form for your drug.
  • Give the form to your provider to complete and send to Express Scripts.
    • Instructions are on the form.
    • You don’t need to send multiple forms.

Prior authorization approvals will apply to military pharmacies, home delivery, and network pharmacies. Medical necessity approvals apply to home delivery and network pharmacies.

Can’t find the form you need? Contact Express Scripts.

Step Therapy

You must use step therapy with certain prescription drugs. This means you must try a preferred drug as the first step in treating your medical condition.

The preferred drug is:

  • Safe
  • Clinically effective
  • Cost-effective
  • Often a generic drug

You can get non-preferred drugs, but only if the preferred drug isn’t effective or tolerated well This means you must try the preferred drug first.

If you’ve tried the preferred drug in the last 180 days, you’ll get automatic approval for the non-preferred drug. Once approved, there’s no expiration date

Prescription Quantity Limits

Quantity limits vary by type of pharmacy:

Exceptions can be made if your provider establishes medical necessity.

Last Updated 9/28/2026