- Catecholamines
- Causes of Substance Abuse
- Center on Addiction and Substance Abuse (CASA)
- Centre for Addiction and Mental Health
- Child Abuse and Drugs
- Childhood Behavior and Later Drug Use
- Chinese Americans, Alcohol and Drug Use among
- Chloral Hydrate
- Chlordiazepoxide
- Chocolate
- Chromosome
- Chronic Pain
- Civil Commitment
- Clinical Trials Network
- Clone, Cloning
- Clonidine
- Club Drugs
- Coca Paste
- Coca Plant
- Cocaethylene: Immunologic, Hepatic, and Cardiac Effects
- Cocaine
- Codeine
- Codependence
- Coerced Treatment for Substance Offenders
- Coffee
- Cognitive-Behavioral Therapy
- Cola/Cola Drinks
- College on Problems of Drug Dependence (CPDD), INC
- Colombia as Drug Source
- Commissions on Drugs
