Yes. Except where absolute criteria exist, the final determination as to whether the driver meets the FMCSA medical standards is to be made by the medical examiner. The examiner should use whatever tools or additional assessments they feel are necessary. Under 391.43, Instructions to the Medical Examiner -Laboratory and "Other Testing," support is provided to the examiner if they believe that "Other test(s) may be indicated based upon the medical history or findings of the physical examination."
Further supporting the need for additional evaluation is the medical advisory criteria for 391.41(b) 13 which notes that "if an individual shows signs of having an alcohol-use problem, he or she should be referred to a specialist. After counseling and/or treatment, he or she may be considered for certification."
While not regulation, the medical advisory criteria are provided by the FMCSA to assist the Medical Examiner determine if a person is physically qualified to operate a CMV. The Medical Examiner may or may not choose to use these guidelines. These guidelines are based on expert review and considered practice standards. The examiner should document the reason(s) for not following the guidelines.