Is there a list of disqualifying drugs for a Commercial Motor Vehicle driver?

Federal Motor Carrier Safety Regulation 382.107 defines controlled substances as "substances identified in § 40.85". Those substances are:

(a) Marijuana metabolites.

(b) Cocaine metabolites.

(c) Amphetamines.

(d) Opiate metabolites.

(e) Phencyclidine (PCP).