Teenage depression – Beware of alcohol and marijuana use!

As a psychiatrist who specializes in alcoholism and addiction, I treat a number of depressed college students with antidepressants. This age group tends to experiment with drugs and alcohol. I have observed over the years of my practice that the antidepressants I prescribe do not seem to be as effective in someone who uses marijuana and/or alcohol, even if the use is infrequent. Here are 2 cases I’ve dealt with that illustrate this point.

Case 1: I treated a 19 year old college boy for anxiety and depression. He said that he occasionally used marijuana to calm down before a social event (weekly or every other week) because he felt more comfortable around people when he was high. He did not respond to two different antidepressants that I prescribed for him over the course of 12 weeks. I told him that his marijuana and alcohol use on the weekends could be interfering with the effectiveness of the medications. He agreed to go without marijuana or alcohol for a month. Sure enough, his social anxiety began to subside even though he hadn’t changed his antidepressant dosage or added any new medications. He experienced a significant reduction in anxiety and depression and has not returned to marijuana or alcohol. He reported that he attended social functions, had a great time, and felt more self-confident than when he first came to see me.

Case 2: I treated a 21-year-old college girl for depression who was out drinking with her friends on the weekends. She said that she used to drink to numb herself and escape her feelings of depression. She didn’t drink anything during the week. I prescribed the same antidepressant that had worked for her when she was 14 years old. However, after 6 weeks on a therapeutic dose, she was still depressed. At 14, she didn’t drink alcohol. I explained to her that alcohol was a central nervous system depressant and she was probably counteracting the effects of the antidepressant. I asked her to stop drinking and let the medication do the work for her. She agreed to this because her depression had been getting progressively worse for several weeks and she was miserable. Four weeks later, she was feeling much less depressed. She reported that she was looking forward to the day, finding it easier to keep up with her work and participating in more activities with her friends.

Both cases provide anecdotal evidence that the antidepressants I prescribe for depression or anxiety don’t seem to be as effective when my college patients are actively using alcohol or marijuana. When I prescribe medication to a college student, I explain to him that it is difficult for me to make positive biochemical changes in the brain with the medications I prescribe when the substances he is using counteract the positive effects of the medications.

Research on adolescent depression with substance abuse has tended to focus on adolescent drug abuse or alcohol use at the level of abuse or dependence. There has not been much focus on the recreational use of marijuana or alcohol in this population. What are the dangers of marijuana and the dangers of alcohol consumption when used at low levels?

Reduced antidepressant response.

The findings of a very recent study, conducted by Dr. Benjamin Goldstein and others at the University of Pittsburgh, dealing with depressed adolescents who used marijuana and alcohol recreationally, support this. The study was presented October 26, 2009 at the American Academy of Child and Adolescent Psychiatry and was summarized in Medscape Medical News. The study showed that the antidepressant response was significantly reduced in depressed adolescents who used marijuana or alcohol recreationally. They studied 334 adolescents with major depressive disorder, 28.1% of whom used marijuana or alcohol recreationally. The researchers also found that those who stopped using marijuana/alcohol during the study showed a good response to antidepressants and those who started using marijuana/alcohol during the study had a reduced response to antidepressants.

I wouldn’t be surprised if the findings described in Dr. Goldstein’s study on adolescent alcohol and marijuana use apply to college youth and even older adults.

Here’s the take-home message for depressed teens on antidepressants:

you use, you lose

In other words, you lose the antidepressant response. Remember, the recreational use of alcohol and marijuana interferes with the antidepressant response.

If you want to feel better, let the antidepressants do their work on your brain without mixing their effects with other drugs you want to experiment with. According to this study, antidepressants are more effective for your age group if you do not use drugs or alcohol.