Rich Powell, who teaches in UCSB’s Department of Exercise and Sports Studies, sat for questions from Carla Amurao, a student of film and of sociocultural linguistics. Powell is a member of the UCSB Drug Task Force, which provides information to students on “the pharmacokinetic and pharmacodynamic action of psychoactive recreational drugs.”
What medical use does marijuana have?
In terms of medical applications, there are all kinds-some of them are more anecdotal, others have been proven to be effective in terms of health applications. People use [cannabis] for insomnia, anxiety, controlling spasms, migraines, headaches. Supposedly it relieves glaucoma, you know, with pressure behind the eye, controls pain and nausea with certain types of cancer, and it’s used as an appetite stimulant for people with AIDS. Those are the main ones.
So what is the difference between abuse and dependence, if there is one?
There are some issues related to physical dependence, but they don’t tend to be as apparent as with drugs like alcohol and other psychoactive substances. Over the last decade we’ve seen increases in the THC content of cannabis, and as a result of that we’ve seen more of our students and more people in the community coming in for help in terms of withdrawals and trying to stop use. But for the most part we would have to say that cannabis produces dependence in a different way than other kinds of drugs; basically it’s more of a psychological thing, though there are some physical components-sleep disturbances, anxiety, some depression.
So one of the questions probably you have to ask is, “Does the drug produce dependence?” Absolutely. “Addiction” is another term that I don’t think works quite as well with this drug as “dependence” does.
What is common for users experiencing withdrawal symptoms?
Many times we will see some acute phases with what’s called “acute phase withdrawal” symptoms. But heavy users of the drug tend to have problems in what we would say would be the “latent phase” withdrawals area, which would be after they stop for 30 days or more. You would start to see some strong psychological kinds of dependences that occur, especially if they’re in the wrong environment, like an environment where people are using, or if it’s available. It’s difficult to adjust to that.
What are the drug’s short and long term effects?
The effects vary from user to user. The naive user (the occasional user) is going to have different effect than your regular user.
In the short term, you would see paranoia, nervousness and anxiety associated with its use. As a person develops more tolerance for the drug and they use for a longer period of time, we’re going to see some negative things that are associated with the cardiovascular system, and those things are really associated with lack of oxygen to the red blood cells, and as a result of that the heart has to work harder to produce the cardiovascular system with more oxygenated blood. We’re going to see some residual kinds of accumulations of tar in the lung linings, which tends to be quite common with people who use on a regular basis.
As a result of long term use, we’re seeing some evidence of some changes in the brain’s neurotransmitters. So whether you want to call that brain damage or not-I don’t tend to associate it with brain damage, but I do see it as changes to the brain. Whether the brain will come back to normal or not, to the way it was before-it may or may not. For most people who use for a number of years on a regular basis, there’s typically no problem in terms of recovering and coming back to normal. But over the long term, we may see issues related to that and personality changes associated with its use as well.
How long does THC stay traceable in urine, blood and hair?
Urine’s going to show typically anywhere between 20 and 30 hours. That’s the typical half life of this drug when it’s smoked and that’s going to vary depending on the frequency of use. The regular user tends to metabolize the drug faster than your naive user, so the occasional user would have a longer half life.
They rarely take hair samples [for drug testing], but hair samples would be a longer period of time. You’d probably be able to pick it up for 6 months after smoking, depending on when the last hair cut was. The blood would be able to pick it up a little longer than 30 hours.
Could you briefly discuss other ways one could take in THC?
Gastrically, it gets absorbed into your system through the stomach, and that tends to have a different effect. I’m not sure of the half-life of gastric absorption. There are ways of taking it in through your skin, like being exposed to it at a party. You can get some effects from it that way as well, and you can test positive being a non-user.
What about users who justify themselves by saying that you could never die from a marijuana overdose?
It’s very possible. I’ve never heard of a case unless there was a genetic predisposition associated with a cardiovascular issue, but this is the kind of drug that we don’t see people tending to overdose on.
I’ve heard that smoking the stem of the plant could cause infertility. How does frequent use interfere with sex hormones?
Some studies have indicated that you see compromise in white blood cell counts, which are our cells that fight bacteria and other kinds of infectious diseases. Those studies are also correlated with sperm count dropping in men as a result of smoking. So those are the only studies I’ve seen which have indicated some evidence which support that sperm counts would be compromised. In terms of sex drive I haven’t seen anything on that before. There are some things related to alcohol that I know about, but not in terms in use of marijuana.
In a college atmosphere, it is common for people to claim that they perform better academically, or just in everyday activities, while under the influence. How is this possible, if it is possible?
It can be true if these people are using everyday on a regular basis and they’ve already really adjusted to the drug and developed a tolerance for its effects. So I guess, to answer that question, if you’re using on a regular basis and you’re studying on a regular basis with the drug on board, you probably want to continue to do that [laughs], but if you’re a naive user or an occasional user and you use it before you study you probably wouldn’t have the same result. Now is it going to be an advantage to use it? I would probably say it’s only going to be an advantage if you’re a regular user to continue that kind of use. It may or may not be, depending on dosage, the kind of THC content that you’re using, and that’s going to vary from person to person.
Many people attribute their antisocial tendencies to frequent marijuana use-is this generally a common social problem?
There’s a kind of psychosocial issue related to it. Our students that use cannabis heavily on a regular basis—we see some isolation with these people. They don’t tend to isolate in terms of being alone, but they tend to always gravitate towards the same groups of friends. We have seen, just anecdotally, that they don’t tend to reach out to develop new social stimulators.
So what would you say is worse-regular use of tobacco or marijuana?
You’d probably have to say that it would be tobacco, depending on the delivery device. The delivery device for both of those mechanisms of getting smoke on board is really associated with most of the damage in terms of health risks, delivery device being whatever you use to get the smoke on board. The cooler the smoke is, the less damage [it causes], and if you have any protective mechanisms in between you and the smoke that’s going to be important as well.
We really want you to understand that cannabis is not a benign drug; there are some side effects with the drug that can be somewhat serious in terms of psychological and physiological issues. But you’d probably have to say, at this point, tobacco. Because it’s more frequently used than cannabis for the most part, in most people tobacco would be probably much worse for you.
Is it true that marijuana today is more potent than in the 60s?
Yes, absolutely. I think that they’ve just pretty much learned-I’m not an expert on growing it-but the cultivators have learned how to get the most THC in the plant, and as a result of that it’s been an evolution, you know? I’ve been here since 1983, and since that time there’s been a lot more students coming in to health services for counseling with the use of this drug than we did back then. We used to have a lot of users back then, but we tend to see a lot more students coming in who are having problems with the drug today.
Some people have claimed that in some cases it’s easier to get marijuana than it is to get alcohol. Do you think that there are more people coming in for counseling because the drug is stronger or because it has become easier to acquire it these days?
I think it was pretty easy to get back then, if not easier. I could be wrong, but I think it’s because the potency is up.
Why is it that clubs like NORML can hold joint rolling contests at a local Isla Vista park? Blunt rolling has come to be considered a dying art. Marijuana use is constantly referred to in songs and movies. So why don’t we just legalize its use since it’s such a big part of culture and society?
That is a tough, sociological question. My expertise area is more pharmacological, not really sociological. You have to go back and ask your questions, “Why would a drug like alcohol be legal and cannabis not?” or “Why would tobacco legal and cannabis not?” Those are the questions you kind of always have to go back to. The drug laws that we have in the U.S. are supposedly based on pharmacology, but many of them are based on the political climate of the U.S. and drug trafficking laws are kind of supporting those things. I think that it’s probably important to know that our drug laws are, in many cases, politically driven.