DATA ON BOTH FEMALE AND MALE DRUG ABUSERS WERE EXAMINED TO DETERMINE IF THERE ARE SEX-SPECIFIC DRUG USE PATTERNS, DEMOGRAPHIC VARIABLES, AND PSYCHOLOGICAL CHARACTERISTICS. RESULTS OF THE HOUSEHOLD SURVEYS, CONDUCTED IN 1975-76, INDICATE THAT FOR ADULTS (AGE 18 OR OLDER) NO SIGNIFICANT DIFFERENCES WERE FOUND BETWEEN MALES AND FEMALES REGARDING CURRENT ILLICIT DRUG USE, EXCEPT FOR MARIJUANA WHICH MALES USED TO A GREATER EXTENT THAN FEMALES. MALES' USE OF ALL ILLICIT DRUGS IS SIGNIFICANTLY HIGHER THAN THAT OF FEMALES, WHO REPORT GREATER NONMEDICAL USE OF PSYCHOTHERAPEUTIC DRUGS THAN MALES. FOR YOUTHS AGED 12 TO 17, FEMALES REPORT SIGNIFICANTLY LOWER USE THAN MALES OF INHALANTS, MARIJUANA, AND HASHISH. FURTHERMORE, DRUG ABUSE WARNING NETWORK DATA REPORT THAT A SUBSTANTIAL PROPORTION OF THE DRUG PROBLEMS ENCOUNTERED BY WOMEN ARE CAUSED BY THE MEDICAL USE OF PSYCHOTHERAPEUTIC DRUGS, PARTICULARLY BARBITURATES AND AMPHETAMINES. TREATMENT DATA INDICATE THAT FEMALES ENTERING TREATMENT ARE LESS LIKELY THAN MALES TO BE USING HEROIN, METHADONE, ALCOHOL, OR COCAINE AND MORE LIKELY TO BE ABUSING PSYCHOTHERAPEUTIC DRUGS. ALSO, FEMALE CLIENTS, AS OPPOSED TO THEIR MALE COUNTERPARTS, ARE LESS LIKELY TO BE BLACK, PUERTO RICAN, OR MEXICAN AMERICAN; LESS LIKELY TO BE EMPLOYED; AND LESS LIKELY TO HAVE BEEN ARRESTED. BASED ON THE DATA, IT APPEARS THAT LONG-TERM, OPIATE-ORIENTED TREATMENT PROGRAMS MAY NOT BE APPROPRIATE FOR A LARGE SEGMENT OF THE FEMALE DRUG-ABUSING POPULATION. MORE WOMEN WOULD BE ENCOURAGED TO PARTICIPATE IN DRUG TREATMENT PROGRAMS IF THE SERVICES OFFERED WERE MODIFIED TO MEET THEIR NEEDS. SUGGESTIONS FOR PLANNING THE TREATMENT OF DRUG-ABUSING WOMEN ARE OUTLINED. CHAPTER NOTES, 25 DATA TABLES, 1 FIGURE, AND OVER 100 REFERENCES ARE SUPPLIED. (AUTHOR ABSTRACT MODIFIED)