With the aging of the marijuana generation came the birth of the cocaine generation.

"They're faced with issues like declining sexuality, declining interest in what they're doing, the need for more energy, and wanting to remain young forever," said Dr. Mark Gold, founder of a national cocaine hotline in New Jersey.

Many of these cocaine users had already crossed the legal-illegal barrier by smoking marijuana. They wanted quick solutions to their problems, not long sessions with psychiatrists. "The yuppies," said Gold, "were not psychoanalytically inclined."

These people were seeking an "upper," but in the United States in the 1970s, amphetamines -- the drugs used to give an energy boost -- were recognized as dangerous because of the highly successful "speed kills" campaign. Heroin was associated with needles, a point at which many drug users draw the line, although both heroin and cocaine can be either snorted or injected.

A study published by the National Institute on Drug Abuse, "Cocaine Use in America," bolsters the view that many cocaine users are people who used marijuana and may have become bored with it. Some studies suggest that a person's ability to become high from marijuana declines with age, or with long-term use.

"The population at greatest risk of cocaine use is the population which has used marijuana," the 1985 NIDA report said, "especially those individuals who have used marijuana 100 times or more."

The NIDA report contains 14 scholarly papers on cocaine abuse. In one of them, called "In a Blizzard or Just Being Snowed?," epidemiologist Richard R. Clayton of the University of Kentucky concluded that there are many myths about the drug, including the notion that "practically everybody is using it."

"One need only examine the epidemiological data to know that this is not true," he wrote. According to a Washington Post poll last year, 91 percent of Americans had never tried the drug.

That, however, leaves roughly 22 million Americans who have tried it -- the same estimate cited by federal officials. Even if only 2.5 percent of those people become addicted or otherwise run into problems with the drug -- a conservative estimate, Clayton wrote -- 550,000 people, or roughly the population of Boston, would be at risk.

Cocaine-related deaths also are increasing. In the District, police said, the number of cocaine-related deaths, including drug trade murders and overdoses in combination with other drugs, increased from three in 1981 to 92 last year. In only five cases last year did an overdose of cocaine alone cause a death, but 50 deaths resulted from a combined overdose of cocaine and heroin.

Two surveys of callers to Gold's cocaine hotline in 1983 and 1984 showed users getting younger, and more women using the drug.

The average age of callers in 1983 was 31, compared with 28.5 in 1984, according to a random poll of 200 callers. And while only 24 percent of callers in 1983 were women, 42 percent were in 1984.

The proportion of callers using freebase cocaine, the variety that is smoked and therefore more potent, increased from 16 percent to 27 percent in the period.

"These and other numbers we are so fond of citing and noting represent real people," Clayton wrote in the NIDA study. "In this instance, they are people who are hurting, people who need our help, our concern, our understanding, and our love." Getting Help

People who believe they have a cocaine problem may call 1-800-COCAINE, a national hotline that will refer them to treatment centers in their area. Locally, Narcotics Anonymous runs two hotlines: 338-7989 in the District and Virginia suburbs, 731-7221 in Maryland.