BW: How does medication treat drug addiction?
JF: One approach is to go in and block the brain receptors and transporters that are affected by drugs of abuse. The approach is trying figure out which transmitter systems are involved, and target the medication at those transmitters’ systems. If we know that a longtime cocaine abuser’s system decreases the receptors and the amount of dopamine released, treatment would be to affect the dopamine system. How can we build up the dopamine system? We go and look at different brain systems. Can we go out and repair the systems that have been affected by chronic use and addiction?
The other strategy is to find genetic markers to determine if an individual is going to be responsive to this treatment or not. We can use brain imaging to see which individuals respond to treatment and which [do] not. We use functional MRI and PET [positron emission tomography] studies to measure what systems are effective. NIDA Director Dr. Nora Volkow uses PET imaging to look at the receptor systems, how they are affected by drugs of abuse.
We have a pretty good sense of how drugs of abuse affect the system. [But what we don’t know is] does the brain normalize when they stop? Can we get it back to where it was beforehand? Do these brain changes affect the behavior?
JF: We know that drugs of abuse can affect cognitive processes, learning, and memory. We see the brains of drug-addicted people have receptor deficiencies. But how about when you’re in treatment — do these systems come back online, do you see a functional change? It’s always important to see the structural changes — how these changes in the brain correlate with changes in behavior. Brain imaging gives us insight into how the brain changes are affected by drugs and might be affected by treatment. And in addition to uncovering generic markers, brain imaging is uncovering neurobiological markers. If we could look at someone’s prefrontal cortex on a behavioral task and measure brain responses of drug-addicted individuals versus a control group, can we make some predictions correlated with brain changes? Can we predict how people will do in treatment?
BW: What about prescription drugs? Do you deal with prescription drugs, too?
JF: They work on the brain the same way, and cause addiction the same way. There are plenty of medications, like morphine, which has been a tremendously effective analgesic, but in the hands of someone abusing it you do run the risk of addiction. That should play into a doctor’s prescribing. We are researching the effects of prescription drugs and looking at the same kind of questions we look at [with] other drugs. It’s not off the table — just like we study addiction to nicotine, which is legal.
BW: You are researching the impact of drug abuse and pregnancy. What have you found?
JF: Generically, one can say that taking any foreign substance during pregnancy is not a good thing. We are studying drug exposure during pregnancy to try to find the effect on the developing fetus and the child. There are subtle changes — we have shown that there are some changes in birth weight, birth size, etc., and attention, learning, and memory. Sometimes they are subtle and they may go away. As the kids get older we are trying to figure out if these are “life sentences,” which hopefully they are not, given the right environment and right nutrition, etc. Maybe these effects might be minimal, and that is a good thing!
Another question that’s important: If you have been exposed early on, does that put you at risk for becoming more vulnerable to drugs later? Are you more likely as a teenager?
BW: You are also looking at drug abuse and the teenage brain. When is drug abuse most harmful? Is there an age where it’s less harmful?
JF: The earlier one starts with drugs, the more likely you are to become addicted. Vulnerability increases at age 12,13, 14 to be using drugs, and they are much more vulnerable to addiction. If we could keep kids from starting drugs at age 25 or older, we would find less problems with addiction. Not to say that if I start at 45 or 50 I would be totally protected, but statistics show that the earlier you start, the more likely it is you will become addicted.
I think there are critical times in brain development where drugs may have more influence than others. We also know the young brain tends to be a system in the “go” state, a state characterized by reward. The frontal areas develop last. These do the more executive function — the inhibitory control mechanism. A teenager might not think, “I could get in trouble, I might not get into the college of my choice,” as opposed to the “go” saying, “To heck with my future, I am in the moment right now, and I want to do it.” We know the adolescent’s brain doesn’t have the inhibitory systems. We know that the drugs of abuse affect those brake pads. The frontal regions are highly involved, and if drugs of abuse weaken those systems, and if you have weaker systems to start out, you could be in trouble as a teenager. That’s why we are working really hard to come up with effective prevention strategies so that kids don’t start taking drugs and run that risk of becoming lifelong drug abusers
BW: How can parents prevent drug addiction?
JF: Parents should try their best to educate their kids early on [about] drugs and unprotected behavior. Monitor them and be aware there will be instances where they will be tempted.
BW: What about children and prescription drugs?
JF: We have to keep in mind that there are these things we call drugs and clump them into one category. Medications are very effective at treating whatever the medical issue is when prescribed properly and adhered to properly, [as opposed to] if you take a medication for nonmedical purposes. We can’t lump everything together and say all medications are drugs and drugs are bad. I’ve seen firsthand where kids very near and dear to me needed drug medications and wouldn’t function without them.