DNA: The genetic code of an organism. A long CHAIN molecule of sugar and nitrogen found inside each cell of every living organism (and some viruses).

Deep kissing: The mutual and intense touching or caressing of tongues and lips for a fairly long period of time. This results in the transfer of saliva from one person to the other, which in turn could spread HIV infection if either person is HIV positive and the other has mouth sores.

Detoxifications: The process by which an individual who is physically dependent on a substance is withdrawn from it, often by gradual administration of decreasing doses of the drug of dependence or of a cross-tolerant drug. The primary objective of detoxification is to relieve withdrawal symptoms while the patient adjusts to a drug-free state.

Diagnosis: The process of determining the cause and nature of an illness.

Dormant: Inactive.

Double blind study: Method of medical investigation whereby neither the subject not the investigator knows what treatment, if any, the subject is receiving.

Dose: Amount of a substance or medication that is given at one time.

Drop-in center: A safe and supportive environment where counseling and support services are available to people with alcohol, drug abuse, personal or social problems or otherwise special needs.

Drug resistance: Decreased susceptibility to a drug.