M EX = Medical Exception - This means the member or treating physician or health care professional must obtain a medical exception from Aetna, in order for the medication to be eligible for coverage. Medical Exception criteria apply to non-formulary drugs for members enrolled in or covered by closed benefits plans.  It also applies to Step-Therapy drugs in cases where a member's physician believes it is medically necessary for the member to use a step-therapy drug in the first instance without a trial of the prerequisite alternative drug(s).  Medical Exception may also apply if Precertification applies to a drug and if  it is medically necessary for a member to be treated with a medication(s) subject to precertification that falls outside those precertification criteria requirements.  The member or the member’s treating physician may contact the Aetna Pharmacy Management Precertification Unit to request additional review for medical necessity.