Psychotropic medications, side effects

Psychotropic medication side effects, e.g. metabolic syndrome from antipsychotics. 

In this appendix we discuss a potentially problematic area the identification of, and response to, psychotropic-induced side effects. The most obvious danger of failing to accurately differentiate medication side effects from a disease process is the possibility that one might increase the dose of the very medication responsible for the the side effects. Similarly, unwarranted diagnoses may be assigned or unnecessary medications added. 

Ethnic differences in CYP2D6 have been more thoroughly documented than with the other isoenzyme (Bradford, 2002). Over 70% of Caucasians but only about half of Asians, Sub-Saharan Africans, and African Americans have fully functional CYP2D6 alleles - alleles that code for normal metabolic activity. Approximately 50% of Asian and people of African ancestry have reduced function or nonfunctioning alleles. As a consequence, many older psychotropic medications are metabolized more slowly and plasma levels would be higher. Thus individuals of African and Asian ancestry would have an increased risk of side effects and should receive lower dose for a therapeutic response when compared to Caucasians of European descent (Lin, 2001 Lawson, 2000). 

What Is a Side Effect This chapter picks up where Chapters 1 and 2 left off. As we discussed in the earlier chapters, all medications, psychiatric and otherwise, have multiple effects. One takes a medication to achieve a therapeutic effect. Occasionally, a single medication may have more than one therapeutic effect. All other effects are side effects. Different medications may have differing therapeutic and side effects depending on the intended use. For example, trazodone and quetiapine are often prescribed to aid in sleep, and in this instance sedation is the desired effect, yet when used as an antidepressant and antipsychotic, respectively, the sedation is often an unwanted effect. Psychotropic medications typically have multiple effects. First, they usually interact with more than one nerve cell protein, be it a transporter or a receptor. Quite often, one of the medication s receptor or transporter interactions produces the therapeutic effect. The other interactions tend to not be involved in the therapeutic effect and only serve to produce side effects. Sometimes a neurotransmitter will have multiple different receptor types, but the medication interacts with... 

As we move forward with our discussion, we ll devote a section of this chapter to each of the key neurotransmitter systems that psychotropic medications interact with. We will discuss the following systems norepinephrine, dopamine, serotonin, GABA, acetylcholine, and histamine. Within each of the sections is a description of the effects that can be anticipated when a medication enhances the activity of that transmitter (reuptake inhibitors or agonists), and the effects to expect when a medication interferes (receptor antagonists) with the activity of that same transmitter. We will then describe strategies that can be implemented to help minimize and/or manage these side effects. 

Parkinsonism. As will be discussed later, dopamine-blocking antipsychotics and rarely other psychotropic medications can produce symptoms that resemble Parkinson s disease. This includes an expressionless face, slowed movement, and a stooped posture. In many respects, medication-induced parkinsonism resembles both depression and the negative symptoms of schizophrenia. Again, one must decide if it is the illness or the medication. Do you decrease the medication to remedy the side effect Or do you increase the medication to treat the illness, anticipating that a higher dose may prove more beneficial (though this is not always what is found) ... 

Donovan et al. (1996, 1997) completed an open study evaluating the use of valproic acid (Depakote) in adolescent outpatients with marijuana abuse or dependence and explosive mood disorder (mood symptoms were not classified using the DSM FV Diagnostic System). Eight subjects were prescribed 1000 mg of valproic acid (Depakote) for 5 weeks, in addition to regular therapy sessions, but did not receive any other psychotropic medications. All subjects showed a significant improvement in their marijuana use (p <0.007) and their affective symptoms (p < 0.001), although both outcomes were measured only by self-report. The most common adverse events were nausea and sedation. No subjects discontinued because of these side effects, nor were there any reported interactions between the valproic acid (Depakote) and substances of abuse. 

Other medications, which will not be discussed in the following chapters, have psychotropic actions that are considered to be side effects or adverse effects. Thus, some antihistamines (Le. products used to counteract allergic reactions) induce fatigue and drowsiness, and the same applies to some myorelaxants. Older antihypertensives (Le. agents reducing blood pressure) such as alpha-methyldopa (Aldomet ) or clonidine (Catapres 1) can cause fatigue and depression. 

Side effects of medications, often not recognized as such by patients or inadequately inquired about by the clinician, also complicate adherence to therapy. The delay or time lag in the onset of action of many psychotropics, as well as a delayed time course for a recurrence triggered after stopping medication, also contribute. In this regard, the concept of prevention and prophylaxis must be carefully reviewed with the patient. Finally, the implications for various treatment costs related to compliance need to be explored and the means to circumvent impediments to a patient s cooperation sought (see Cost of Treatment later in this chapter). 

In SUMMARY, it can be seen that the types of psychotropic drug medication that may be used in the elderly are essentially similar to those used in the younger adult patient. The main difference lies in the reduction in distribution, metabolism and elimination of the drugs, which necessitates their administration in lower doses initially followed by a slower escalation of the dose until optimal benefit is obtained. Side effects, particularly anticholinergic effects, are more pronounced in the elderly and can... 

Advokat CD, Mayville EA, Matson JL. Side effect profiles of atypical antipsychotics, typical antipsychotics, or no psychotropic medications in persons with mental retardation. Res Dev Disabil 2000 21(l) 75-84. 

A complex, diffuse symptoms affecting all bodily systems. This is a complex, widespread neurotransmitter, the receptor sites of which are affected (usually adversely) by some psychotropic medications (anticholinergic side effects). 

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