EXCLUSIVE

The banned substance that triggered a WWE wellness policy violation for Eva Marie is Adderall, but we're told Eva is adamant she had a prescription, and will appeal the punishment.

As we previously reported, Marie was hit with a 30 day suspension this week for allegedly violating the policy -- which covers everything from substance abuse to annual physicals and cardiovascular health.

Our WWE sources tell us ... all performers are REQUIRED to disclose all medication to WWE officials for company approval.

We're told in Eva's case ... the WWE claims the medication was NOT properly approved, thus the violation.

Sources connected to Eva say she claims she has a legit prescription from her doctor.

We reached out to Eva, and she said ... “I am disappointed that this suspension has occurred, yet understand and respect that WWE upholds their Wellness Policy to the letter and won't compromise on its integrity."