For some, cocaine is too frenzied. For others, heroin is too mellow. Consequently, Americans are dangerously mixing the two - one a stimulant, the other a depressant - in the quest for that "perfect" high.
Called a "speedball," the mixture has been around since the days of Led Zeppelin. But a rash of deaths in Houston, 15 in two days, points up the enduring popularity of the narcotic cocktail - and the dangers of using it.
Across the country, drug users are increasingly winding up in emergency rooms as a result of speedball overdoses - and many believe an increasingly potent heroin is to blame.
The trend is raising wrenchingly familiar questions about what it is that tempts people to experiment with such potent alchemies - and what cities and families can do to prevent it.
"Nationwide, we are seeing more overdoses from speedballing," says H. Westley Clark, director of the Center for Substance Abuse Treatment in Bethesda, Md.
While cocaine continues to be a problem, heroin has become a growing culprit in the number of overdoses nationwide. In the past year, emergency room visits for heroin overdoses increased by 15 percent, while cocaine visits - still the most frequent - remained stable, according to the annual Drug Abuse Warning Network report.
The reasons are simple. In the past 20 years, heroin has become cheaper, more pure, and easier to administer. So users can't be sure if what they are taking is 20 percent pure or 80 percent pure - especially when mixed with another drug such as cocaine. That makes it even more dangerous, particularly for the unwary.
"Historically, it is normally a single pure drug that causes these kinds of deaths," Harris County Chief Medical Examiner Joye Carter told reporters earlier this week. "A combination is new."
While purer heroin is becoming more common, most street heroin is "cut" with other drugs or substances such as sugar, starch, or powdered milk.
Authorities are trying to determine if anything else was laced with the Houston mixture, but early medical reports indicate the culprit in this mix was the heroin itself.
Clearly, the dangers rise when illegal drugs are combined. A recent study in San Francisco found that experienced heroin users reported having at least one overdose while using speedballs.
While some generalizations can be made about speedball deaths nationwide, the numbers involved in the Houston case are unusual. "You don't see this many people dying in such a short period of time," says Dr. Clark. "It really was extraordinary."
Indeed, it was a record number of overdoses for Houston. The city typically sees two to three drug overdoses a weekend, not all of them fatal.
And while most of last weekend's victims were working-class Hispanics, heroin has grown increasingly popular with suburban teens. "We have a horrible problem with kids using heroin," says a nurse with the Office of National Drug Control Policy in Washington. "They wouldn't stoop to injecting, but now they can snort the stuff."
Last year, in fact, the federal Department of Health and Human Services reported the highest levels of heroin use among high-school seniors since the survey began more than 20 years ago.
That worries many in the field, because not only is heroin the most rapidly acting of the opiates, it is also the most addictive.
While heroin continues to be a problem nationally, Houston doctors are noticing a spike in the number of fatal cocaine overdoses as well. Last month, 31 people died from cocaine overdoses, compared with two in July 2000. And in June, there were 29 cocaine-related deaths, compared with three the previous June.
In these most recent overdoses, authorities are trying to determine if the victims knew they were taking speedballs. Most were not known heroin users.
Back in 1985, says Clark, a similar cluster of heroin deaths - 24 in total - occurred over a five-day period in Washington, D.C. In those cases, police found that the victims were inexperienced with heroin.
Mexican black tar heroin, called that because of its dark color and consistency, is the most common variety in Houston. It is typically about 40 percent pure, but batches from Southeast Asia and Colombia can be as high as 90 percent.
The federal Drug Enforcement Administration is working with the local authorities to try to determine where the drugs came from and whether they have spread outside the state.