Antipsychotic Medication: A User's Guide - Part I
(Column: Ask the Doctor)
I'm going to alter the usual format of this column and instead of responding to questions from the readership, take on a task I was asked to pursue by the New York City Voices' Editorial Board. I would like to discuss antipsychotic medications -- what they are, what they do, how they affect one's body and how each one differs from the others. Naturally, by trying to squeeze all of this information into one or two columns, I won't be able to talk about each medication in any great detail. However, as usual, if you send your questions via E-mail to firstname.lastname@example.org, or by mail, I will be happy to address them individually in future columns.
Psychosis is a state where you experience unusual or strange changes in the way you sense and perceive things, or in your thoughts, feelings, or behavior. Things like hallucinations, delusions, and some kind of confusion are examples of symptoms of psychosis. Probably the best-known psychiatric illness where psychosis is manifested is schizophrenia, but people can also become psychotic from taking street drugs, as a result of alterations in their body chemistry, or as part of mania, post-traumatic stress disorder, or other illnesses. Antipsychotic medications are designed to improve or block symptoms of psychosis. They do not cure the underlying illness such as schizophrenia but allow people to have thoughts, feelings and behaviors more like what other individuals experience.
For many years (since the 1950s) a variety of antipsychotic medications have been available. The earliest of these to be used was Thorazine or Chlorpromazine. Over the last decade, we have produced newer "atypical" antipsychotic medications that differ from the older drugs in the way they work, their side effects, and the parts of the brain that they affect. Many of you will have spent time on the older or traditional antipsychotic medications (commonly called neuroleptics). More and more of you will, over the last five to ten years, have been switched to the atypical medications. However, since many folks still take traditional neuroleptics, I'll begin by describing them briefly before going on to the newer and more commonly prescribed medications.
Throughout this article, I will refer to medications by their brand names or common name. What follows is a chart listing the common names and chemical names of both the traditional and newer atypical antipsychotic medications. Doctors usually refer to these medications by their chemical names, but because most people learn only their common names, I will use them from here on.
Brand Name Generic Name
Conventional Antipsychotic Medications -- all of the traditional antipsychotic medications -- work in much the same way. The primary chemical responsible for psychotic symptoms in the brain is called dopamine. All of the older medications were developed by testing to see how effectively they block dopamine in test tubes or laboratory animals. Thus, all of these medications share the same "mechanism of action." By this, we mean that they block the transmission of dopamine between the nerve cells in the brain. Because too much dopamine is thought to be one of the causes of psychosis, these medications therefore are able to reduce psychotic symptoms.
Although these medications are similar in many ways, they also have differences. Some are called "high potency" which means that you only need a very low dose, only a few milligrams, in order to block brain dopamine. Examples of high potency medications -- those where one usually takes something between 2 and 30 milligrams -- include Haldol, Navane, Prolixin, and Stelazine. Other medications are called "low potency." That doesn't mean that they are less effective but only that you need to take a larger number of milligrams to get the same effect. Examples of low potency medications include Mellaril and Thorazine. Other medications fall somewhere in the middle in terms of their strength per milligram.
High potency traditional medications tend to have side effects that involve your muscles. These include stiffness, involuntary turning or twisting of the neck, and what many people refer to as "restless legs," the feeling that you've got to keep in motion or at least involuntarily move your legs. The lower potency medications often cause symptoms like dry mouth and a lowering of blood pressure so that many people become dizzy if they stand up quickly. In general, the older medications have more side effects than the newer ones, which is why many people are being switched from the traditional to the atypical antipsychotic medications.
One advantage of the older medications is that they are widely available in injectible forms, and some have long acting preparations. With these "depot" medications, you can get a shot once every two to four weeks instead of taking pills by mouth every day. Many of you are probably still on these injectible forms of Haldol or Prolixin, as these shots are often combined with oral doses of the newer medications.
In addition to many of the side effects I described above, traditional neuroleptics also have one very disturbing side effect called Tardive Dyskinesia. TD makes peoples mouths, tongues and muscles move involuntarily or sometimes causes strong, uncontrollable winking of their eyes. Every year, about five people out of every hundred who take the traditional antipsychotic develops TD. Although there are interventions for Tardive Dyskinesia, this is a really dreadful side effect and is much less likely to be caused by the newer antipsychotic meds.
Please feel free to continue to write to me with medication and other questions, which I will answer in future columns. Meanwhile, I would like, once again, to thank my close friend and colleague, Peter Weiden MD, for his help with my understanding of medications and for his guidance. He and several others have written a wonderful book, Breakthroughs in Antipsychotic Medications: A Guide for Consumers, Families and Clinicians, which I have consulted extensively in preparing this column.