As used in this subpart the term:
The term physical or mental impairment includes, but is not limited to, such diseases and conditions as orthopedic, visual, speech, and hearing impairments, cerebral palsy, epilepsy, muscular dystrophy, multiple sclerosis, cancer, heart disease, diabetes, mental retardation, emotional illness, and drug and alcohol abuse.
Examples of (1) include certain opiates and opiate derivatives ( e.g., heroin) and hallucinogenic substances ( e.g., marihuana, mescaline, peyote) and depressants ( e.g., methaqualone). Examples of (2) include opium, coca leaves, methadone, amphetamines and barbiturates.
28 C.F.R. § 42.540