Psychopharmacology it Was Only in the 1950s

Psychopharmacology

It was only in the 1950s when psychiatric drugs to treat severe depression were first developed. Prior to that, most people had to suffer with their emotional pain and its attached sigma. Many individuals had to be admitted to mental hospitals. Now, psychiatrists can prescribe any of hundreds of medications for this illness and, in the majority of cases, have successful results.

Monoamine Oxidase Inhibitors or MAOs were the first pharmaceuticals developed. Although they have more side effects than the tricyclic and latest selective serotonin reuptake inhibitors (SSRIs), they are found to be very helpful particularly in "atypical" and treatment-resistant situations. They can "produce dramatic improvements in some forms of depression" (Gorman, 1990, p. 83). The generic and brand names of the three marketed in the United States are bedisocarboxazid (Marplan), phenelzine sulfate (Nardil) and tranylcypromine sulfate (Parnate).

The efficacy of MAO inhibitors is generally equivalent to the other classes of antidepressant drugs. Similarly, like other antidepressants, MAOIs may take anywhere from two to six weeks to produce therapeutic effects.

This class of drugs inhibits the activity of monoamine oxidase (MAO), the enzyme that destroys monoamine neurotransmitters (norepinephrine, dopamine or serotonin) in synapses in the brain. The inhibition of this enzyme allows these neurotransmitters to remain active in the brain for longer periods of time, thus correcting an expected deficit in monoamine function (Trujillo, 1996).

However, MAO inhibitors often cause the harmful "cheese effect." Certain foods, such as aged cheeses and red wines contain tyramines, substances similar to catecholamines. These amines can simulate the sympathetic nervous system, increasing heart rate and blood pressure. In mild situations, the patient can have a bad headache, stiff neck or nausea. In severe cases, this reaction can cause blood pressure to increase enough to produce a stroke. Therefore, unless strict dietary guidelines are followed, risk of hypertensive crisis is significant. Other side effects, similar to antidepressants include: dry mouth, sexual dysfunction and drowsiness or insomnia. Pregnant women cannot take MAOs, since they may cause birth defects. When appropriate precautions are exercised, MAOIs are safe and effective antidepressants. The usual dosage for bedisocarboxazid starts at 10 or 20 mg daily and can be raised if necessary to 50 mg. Phenelzine is available in 15 mg tablets and 90 mg or higher may be needed at first to get a good response. Tranylcypromine sulfate comes in 10 mg pills and should be started slowly, working up as much as 60 mg.

Patient education is very important with all antidepressants, but more so with MAOs due to the strict dietary restrictions. The doctor should give the patient a fact sheet and go through the list of foods to be avoided. Patients should also be alerted to take precautions if having any blood pressure problems such as dizziness.

The tyramine content of foods varies greatly due to the differences in processing, fermentation, ripening, degradation, or incidental contamination. Many foods contain small amounts, larger portions are found in foods that are aged, fermented, or left to spoil. Foods and drinks to avoid include: Chianti wine and vermouth entirely and larger portions of red, white and port wine (less than 120 ml; ale and non-alcoholic beers completely and larger portions of domestic beer (no more than 1/2 cup); whiskeys and liqueurs; banana peels; soy bean curd (especially fermented) and broad fava bean pods; all cheese, except for cottage and cream; aged or smoked fish; non-fresh meat and liver (except for fresh chicken liver) -- special precautions should be taken in restaurants; sausage, bologna, pepperoni and salami; sauerkraut; yeast. Patients should be alerted that Chinese foods with MSG can cause major problems. There are also foods that should be eaten in smaller quantities and with caution (Lippmann, 1990 p. 202).

Because of strong marketing efforts as well as the major increase in antidepressant usage, most people have heard of the more recent medications such as the brand names Prozac (fluoxetine) and Paxil (paroxetine). Others are Luxov (fluvoxamine) and Zoloft (sertraline). These are also known as the SSRIs or selective serotonin reuptake inhibitors, because they primarily affect the serotonin.

As noted, the SSRIs inhibit reuptake of serotonin. Reuptake is the first step in the process of deactivating this neurotransmitter in the brain. After serotonin is released from neurons, it is removed from these reuptake sites, located on the cell membrane. SSRIs allow serotonin to remain active in the synapse longer, thereby correcting a presumed deficit in the activity of this neurotransmitter (Trujillo, 1996).

Because SSRIs are more targeted, they have a lower incidence of some of the side effects associated with tricyclic antidepressants and MAOIs (e.g., blurred vision, dizziness, constipation, dry mouth). More important to their current popularity, SSRIs have less potential for overdose than the tricyclics or MAOIs, and are therefore considered safer than these other drug classes. Their most common side effects include trouble sleeping, nausea, and dizziness. Less common side effects include headache, drowsiness, less sex drive, and delayed ejaculation (Yale New Haven, Health Library). They should not be mixed with alcohol, and the doctor should be made aware of other medications being taken.

Although some reports suggest that SSRIs may have more rapid actions than the tricyclics or MAOIs, this does not appear to be the case (Trujillo, 1996). Like other classes of antidepressants, clinical response to the SSRIs may take anywhere from two to six weeks to appear.