In the sad aftermath of John Belushi's death, the nation is learning an arcane new vocabulary of drug use. But terms like "speedballing" and "freebase" are routine in the exotic Hollywood drug subculture, where cocaine and heroin are finding new uses in the celebrity pharmacopoeia. Few observers know more about drug chic than Dr. Ronald K. Siegel, a research psycho-pharmacologist at UCLA. Trained at New York's Albert Einstein College of Medicine, the 39-year-old Siegel has treated numerous drug abusers at his UCLA laboratory and is one of the most street-savvy researchers in the field. He discussed Hollywood's latest drug fad with Salley Rayl of PEOPLE.

Did cocaine kill John Belushi?

With Belushi we had a user who was very ill, whose body was not in good shape, who was suffering from a variety of disorders, including an enlarged heart and obesity. He was not a good candidate to survive a stressful experience like a heavy dose of cocaine, heroin and alcohol. There is no doubt that cocaine is a poison and, in certain situations, can kill. But it was not cocaine alone that killed Belushi.

On his last night, Belushi reportedly engaged in "speedballing." What exactly is that?

It's any combination of an upper and a downer, a stimulant and a depressant. Irish coffee is a speedball. So is rum and cola. But over the last two years on both coasts there's been an increasing attraction to heroin and cocaine taken intranasally—that is, snorted. The heroin counteracts the stimulant effects of the cocaine. It's considered, at least in Hollywood, a very chic thing to do.

What are the risks of speedballing cocaine and heroin?

I would say users are risking unknown effects. They are using two compounds which are potentially toxic and poisonous, and they are mixing them together. We don't even have a clear idea of the pharmacological effect of one of them alone, let alone the interactions between the two. The special danger is that the user feels subjectively safer than with cocaine alone. He thinks, "I'm not as excited, my heart's not beating as fast, I'm not climbing the walls and grinding my teeth, I'm looser." He feels reassured, and so is prone to repeat the experience, thinking more is better. But he's not getting clear signals, and the risk of overdosing increases.

Can this type of speedballing lead to heroin abuse?

The familiarity with snorting heroin has led some people who normally wouldn't go near a needle to experiment with the heroin high alone intravenously. It seems to have started at the same time in two places—the entertainment community in New York and the entertainment community in Los Angeles.

What else is in vogue?

Marijuana and cocaine combinations are increasingly common. People will snort coke at the end of an evening of marijuana smoking to cut the lethargy of the marijuana high and allow them to drive home. It is potentially dangerous because one is increasing only wakefulness, not motor coordination. It's a misleading subjective state. Another common combination is Quaaludes and cocaine. The more cocaine you can use, the more Quaaludes you can tolerate. It wouldn't be uncommon for someone to take eight to 10 Quaaludes a day to balance the cocaine they're doing.

Can large doses of cocaine trigger heart attacks?

That's in the users' minds, because they can feel their heart beat faster, and coke does elevate the pulse rate and blood pressure. It's a rare event, but it can happen.

What about convulsions or deaths?

In the last couple of years we've discovered that high doses of cocaine increase the risk of seizure because of changes in the electrical properties of the brain. But we see most deaths coming from smugglers who swallow a condom or balloon filled with the drug, which bursts in the stomach.

Who are the main users of speedballs?

I see slightly more females than males. They all tend to be in the same professional positions—actors, actresses and movie production people. It's a limited circle—though not necessarily limited by economics. Higher-class users can spend $2,000 to $12,000 a week on coke. It's a habit for achievers.

Why is it so difficult to combat cocaine use in Hollywood?

It is very socially acceptable in this town and almost required. We have a lot of conspicuous consumption out here. We have a lot of people who have a lot of money who buy very exotic, glamorous, high-priced drugs. I have a couple of people I see who are not sure if they really want to quit because it is so mandatory to their positions. They have to dispense it to people they work with. It is almost culturally ingrained in show business, very much like tobacco is ingrained in the armed forces and alcohol is a drug of commerce in much of the business world. Similarly, cocaine is becoming a drug of commerce in the entertainment world.

Do you see cocaine abuse elsewhere?

There is media attention on show business people, so their drug habits become very visible. But I see less visible people in the business community who are just as gluttonous with their use of cocaine and heroin, but they are not as conspicuous.

Freebasing—the practice of smoking purified cocaine for a more powerful rush—reportedly caused Richard Pryor's accident. Is its use decreasing?

Hardly. It's still on the rise, but users have found ways to circumvent the danger of explosions. Cocaine on the street exists in the form of cocaine hydrochloride, a salt that dissolves in water as well as body fluids and membranes in the nose. In the old method, freebasers would mix it with ether or other solvents to "free" the base from hydrochloride salt and various impurities in the cocaine. The base is a smokable form that produces an intense high. When heated, however, the flammable ether mix could easily explode. Now people are substituting nonvolatile methods for the ether.

Why would anyone want to try free-basing?

When you snort cocaine intranasally, it takes approximately three minutes to get into your blood and to your brain. When you inject cocaine intravenously, it takes 14 seconds to get to your brain and you get a faster rush—a rush is the speed with which you change your psychological state. Base is faster. Base takes six seconds. So when you smoke cocaine through free-basing you get high in six seconds, more than twice as fast as injecting. It may not seem like a lot; you're only saving eight seconds, but the brain recognizes that as a significant event.

Are most of your patients freebasing cocaine?

Originally most were, but over the last couple of years we've been seeing a lot more problem intranasal users and people injecting it. The dosages are going up regardless of the form.

Why?

People develop tremendous tolerances to cocaine and need to escalate to get the same kind of high. The minimal lethal dose is estimated to be 1.2 grams taken at once. But I've seen people smoke 3.5 grams of freebase in one hit, or put five grams up their nose at once, and their bodies tolerate it.

Is cocaine addicting?

It is when used in the freebase form. By addicting I mean you have to take more and more to get the same physiological effect, and when you stop taking the drug you precipitate a cluster of withdrawal symptoms. An abrupt cessation of cocaine causes depression, lethargy, overeating and sometimes involuntary muscle movements. It's not a life-threatening withdrawal, but it is a withdrawal.

Are many people switching from snorting cocaine to mainlining it?

We estimate that 15 million people in the U.S. have used cocaine. There are perhaps 10 million regular users, and of them, maybe 100,000 have problems that require clinical attention. But cocaine is injected by less than 1 percent of people who use it. Well over 80 percent use it intranasally.

What does prolonged use of cocaine do to a person's mental state?

Psychosis is still a very rare event for an intranasal user, but we do see people becoming paranoid with high-dose, intranasal use of cocaine. The users tend to progress through three stages. Their first encounters with cocaine tend to be euphoric. They tend to feel elevated in mood. They're loquacious. They have motor excitement, increased sexual interest and they seem able to perform better. With increased dosages and increasing frequency of use, this euphoria gives rise to dysphoria. That is a depression marked by melancholy, sadness, inability to pay attention and concentrate, insomnia, anorexia and lack of sexual interest. As cocaine dosages continue to increase, or stay the same but continue over time, the dysphoria is replaced by paranoia, which can be accompanied by hallucinations and other elements of psychotic thinking.

Does it matter how one uses the drug?

No, psychosis can happen with intranasal use, intravenous use or free-basing. It just takes longer to get there with intranasal use. I once testified in Washington that I didn't believe in cocaine psychosis as a bona fide effect of recreational use. But I am finding it now in people using as relatively little as a gram a day.

Are you in favor of legalizing the drug?

Definitely not. I have never heard anyone responsible say that cocaine should be legalized. I am not saying even that cocaine should be removed from criminal penalties. I am saying that there should remain strong controls in the use of a substance like cocaine, because it does have the pharmacological properties that render it abusable and potentially poisonous. But there should be a little more pharmacological reality in our laws. Right now they have not been rewritten since 1914 with respect to cocaine. They still call cocaine a narcotic. It is a stimulant. Because of that difference, in some states users can get mandatory life imprisonment for a cocaine offense, instead of maybe seven years for a stimulant. This is by no means saying that anyone should be excused from the offense. But given all the problems of cocaine use, the most dangerous aspect of it is getting caught and suffering criminal penalties.