is dihydrocodeine a controlled drug
Regulation. Dihydrocodeine is a controlled substance in the United States. Classified by the Drug Enforcement Administration as a Schedule II substance, it requires federal regulation. Possession without a prescription is illegal, and state laws for possession and penalties vary.epeated and prolonged use of dihydrocodeine may cause the body to develop a tolerance to the drug, rendering it less effective in the treatment of pain. This may result in physical and psychological dependency, causing withdrawal symptoms such as restlessness and irritability.