Defining Psychopharmacology
Psychopharmacology is the scientific study of the effects psychotropic substances have on mood, sensation, thinking, and behavior; psychopharmacotherapy is the medical application of these substances. A psychotropic substance is one that affects the mind or mental processes.
Psychotropic medications seek to address neurological imbalances in the brain that are thought to contribute to specific mental illnesses. The use of psychotropic medications is based on a philosophy held by biomedical therapists that the mind and body are connected, and that imbalances in the brain can be remedied to alleviate symptoms caused by these imbalances. That said, most practitioners prescribing medication for psychiatric symptoms require that their patient also be in psychotherapy with them or with another practitioner to further support the treatment and to provide closer supervision.
There are four major classes of psychotropic medications: antipsychotics, antidepressants, anti-cycling agents, and hypnoanxiolytics. The first three groups of medications target specific problems such as mania or hallucinations. If a "normal" individual took one of these medications they may notice little to no effect because the drugs are intended to target a specific problem that the normal individual does not suffer from. Hypnoanxiolytics, on the other hand, have general effects that work on all individuals.
Antipsychotics
Antipsychotics include drugs such as chlorpromazine and haloperidol. Antipsychotics are used to treat schizophrenia, but also may be used for treating mania, delusional disorders, and other disorders. Antipsychotic medications work primarily by blocking dopamine receptors. They have been found to work for as many as 70% of individuals with schizophrenia; however, approximately 30% of users develop serious side effects from using antipsychotics.
Antidepressants
Antidepressants come in several forms: tricyclics, selective serotonin reuptake inhibitors (SSRIs, such as Prozac and Praxil), and monoamine oxidase inhibitors. Antidepressants are used to treat major and bipolar depression, panic attacks, phobias, and obsessive-compulsive disorder. The most commonly used antidepressants primarily affect the norepinephrine and serotonin (monoamine) neurotransmitter systems. Most antidepressants increase the available amount of norepinephrine or serotonin (or sometimes both) at the neuronal synapse, by decreasing the reuptake of these neurotransmitters into the pre-synaptic cell. They do this by inhibiting the norepinephrine transporter or the serotonin transporter, or by decreasing the metabolism of these neurotransmitters. Other antidepressants have direct effects on monoamine receptors. Antidepressants are effective in approximately 80% of individuals.
Antidepressant
Antidepressants are used to treat depression, panic attacks, phobias, and obsessive-compulsive disorder.
Anti-Cycling Agents
Anti-cycling agents, also called mood stabilizers, are drugs such as lithium that are used to treat bipolar disorder. Lithium is very effective and very fast working: it eliminates the manic phase of bipolar depression, and once the manic phase is eliminated, the depressed phase usually stops as well. The downside is that lithium has a number of serious side effects.
Hypnoanxiolytics
Hypnoanxiolytics include antianxiety agents (also known as anxiolytics), hypnotics, atypical anxiolytics, and atypical hypnotics. Together, hypnoanxiolytics have a general effect of calming individuals, alleviating anxiety, and causing sleep. Unlike the other classes of psychomedication, hypnoanxiolytics have general effects that work on all individuals.
An anxiolytic is a drug that inhibits anxiety (in contrast to anxiogenic agents, which increase anxiety). Anxiolytic medications have been used for the treatment of anxiety, anxiety disorders, and their related psychological and physical symptoms.
Hypnotic drugs are a class of psychoactives whose primary function is to induce sleep and to be used in the treatment of insomnia, as well as in surgical anesthesia. Because drugs in this class generally produce dose-dependent effects, ranging from anxiolysis to production of unconsciousness, they are often referred to collectively as sedative-hypnotic drugs. Hypnotic drugs are regularly prescribed for insomnia and other sleep disorders, with over 95% of insomnia patients in some countries being prescribed hypnotics. Many hypnotic drugs are habit-forming and, due to a large number of factors known to disturb the human sleep pattern, a physician may instead recommend alternative sleeping patterns, sleep hygiene, and exercise, before prescribing medication for sleep.
The hypnotic medications benzodiazepine and nonbenzodiazepine also have a number of side effects such as daytime fatigue and cognitive impairments. However, benzodiazepines are often preferred over SSRIs for the treatment of anxiety disorders because they act more quickly and require a lower dose in order to be effective.
History of Psychopharmacology
Psychotropic substances have been used by humans for thousands of years. With the dawn of the Neolithic Age and the proliferation of agriculture, new plants with psychotropic effects came into use as a natural by-product of farming. Among them were opium, cannabis, and alcohol derived from the fermentation of cereals and fruits. Most societies began developing herblores, lists of herbs which were good for treating various physical and mental ailments. For example, St. John's wort was traditionally prescribed in parts of Europe for depression (in addition to its use as a general-purpose tea), and Chinese medicine developed elaborate lists of herbs and preparations. These and various other substances that have an effect on the brain are still used as remedies in many cultures.
The dawn of contemporary psychopharmacology marked the beginning of the use of psychiatric drugs to treat psychological illnesses. It brought with it the use of opiates and barbiturates for the management of acute behavioral issues in patients. In the early stages, psychopharmacology was primarily used for sedation. Then with the 1950s came the establishment of chlorpromazine for psychoses, lithium carbonate for mania, and then in rapid succession, the development of tricyclic antidepressants, monoamine oxidase inhibitors, and benzodiazepines, among other antipsychotics and antidepressants. Defining features of this era include an evolution of research methods, with the establishment of placebo-controlled, double-blind studies, and the development of methods for analyzing blood levels with respect to clinical outcome and increased sophistication in clinical trials.
The early 1960s revealed a revolutionary model by Julius Axelrod describing nerve signals and synaptic transmission, which was followed by a drastic increase of biochemical brain research into the effects of psychotropic agents on brain chemistry. After the 1960s, the field of psychiatry shifted to incorporate the efficacy of pharmacological treatments, and began to focus on the uses and toxicities of these medications. The 1970s and 1980s were further marked by a better understanding of the synaptic aspects of the action mechanisms of drugs. However, the model has its critics—notably, Joanna Moncrieff and the Critical Psychiatry Network.
Efficacy of Psychopharmacology
Ideally, biological and psychosocial therapies should work together in a complementary fashion. For example, an individual with schizophrenia who is bombarded with visual, auditory, or other hallucinations, may find it difficult to focus in psychotherapy. With medication, the individual's hallucinations can be eliminated or reduced to a level at which the individual can benefit from psychotherapy.
Different disorders respond to drug therapy differently. Some disorders are managed very effectively with biological therapies, others respond better to counseling, and some require the use of both. For example, the primary treatment of schizophrenia is antipsychotic medication, but it can be combined with psychosocial interventions like therapy. Eating disorders, on the other hand, are primarily treated through different types of psychotherapy, though medications related to weight gain or loss may be utilized. Depression is treated with therapy alone when possible to avoid the risks and side effects associated with drugs, but for some patients the combination of therapy and antidepressants is much more effective.
Criticisms of Psychopharmacology
A somewhat controversial application of psychopharmacology is "cosmetic psychiatry." This is when people who do not meet criteria for any psychiatric disorder are nevertheless prescribed psychotropic medication. For example, the antidepressant Wellbutrin might be prescribed to increase perceived energy levels and assertiveness while diminishing the need for sleep, instead of its intended use, alleviating symptoms of depression. The antihypertensive compound Inderal is sometimes chosen to eliminate the discomfort of day-to-day, "normal" anxiety. Prozac in not-depressed people can produce a feeling of generalized well-being. Mirapex, a treatment for restless leg syndrome, can dramatically increase libido in women. These and other off-label lifestyle applications of medications are controversial and not uncommon. Although occasionally reported in medical literature, no guidelines for such usage have been developed.
There is also a potential for the accidental misuse of prescription psychoactive drugs by elderly persons, who may have multiple drug prescriptions.