Psychopathology Sum-Up: Types of Antidepressants

Weekly series! As per previous discussion, I will be publishing a big information blog on each Friday. Unfortunately, it’s midterms for me, which means a shorter post for you. Blame the paper(s) and exams and readings and stuff. I promise to be back on schedule next week. Also, I’ve commissioned a post on bulimia from Tetyana, who runs the spectacular Science of Eating Disorders blog, a skeptical look at research on ED’s.

Anyways, today we look at the types of antidepressants.

Selective Serotonin Reuptake Inhibitors (SSRI’s)

[Note to neurobiologists: I am simplifying massively here. I know that.]

These are the most popular medications for depression, and include a bunch of names you probably recognize: Zoloft, Prozac, Paxil, Celexa, Lexapro.

How do they work?

A general sketch of two neurons.

A general sketch of two neurons.

Neurons don’t connect directly to each other–they have a very tiny space (the synaptic cleft) between each end of one and beginning of the next. Neurotransmitters (like serotonin, dopamine, GABA, etc) are released from the presynaptic neuron, and partially absorbed by the postsynaptic neuron. The neurotransmitter that isn’t absorbed is mainly taken back by the presynaptic neuron. SSRI’s work by blocking the reuptake mechanism for serotonin, leaving more available serotonin in the brain, which seems to relieve depression in some people.

But, this is grossly oversimplified, and depression is not as basic as not having enough serotonin. In the words of Ozy, brain chemicals are not fucking magic.

Side effects of SSRI’s can include lack of sex drive, hyperactivity or lowered energy, etc. In some, these are so life-disrupting that other medications are preferred.

Serotonin-Norepinephrine Reuptake Inhibitors (SNRI’s)

SNRI’s include Cymbalta, Effexor, and Pristiq. They work very much like SSRI’s, except they inhibit both the reuptake mechanism for norepinephrine and serotonin.

The effectiveness of SSRI’s lends support to the Monoamine Hypothesis–an incomplete explanation for depression, suggesting that several neurotransmitter systems (including serotonergic) are responsible.  The hypothesis does hold up to scrutiny, but doesn’t explain why many antidepressants also help with anxiety and obsessive-type disorders.

Tricyclic Antidepressants

Color me happy to have done my research before publishing–turns out I didn’t have all of my facts straight. Tricyclics are antidepressants that operate somewhat like SSRI’s by inhibiting the reuptake of serotonin–but they also have a laundry list of possible side effects, and, like MAOI’s, are used more and more rarely.

Monoamine Oxidase Inhibitors (MAOI’s)

MAOI’s can be super effective! However, they come with hefty diet restrictions, and resultingly, are used rarely–mostly as a last resort.

People taking MAOI’s need to avoid all sorts of things, like pickled foods, most cheeses, wine, decongestants, and SSRI’s. Failure to do so can cause a stroke–the result of buildup of tyramine in the brain. Since other antidepressants are available, MAOI’s have fallen out of favor.

Norepinephrine and dopamine reuptake inhibitors (NDRIs)

Wellbutrin! NDRI’s are good because they usually don’t have the sexual side effects. They too, lend support to the Monoamine Hypothesis, by altering the dopaminergic and norandronergic pathways.

St. Johns Wort

Okay. This is alt-med, but it’s been gaining mainstream popularity. It’s one of those that might work on mild to moderate depression. And if taken without doctor supervision and with other medications it can cause you all sorts of problems. In combination with SNRI’s, it can cause Serotonin Syndrome–an excess of the neurotransmitter which overloads the central nervous system. It also appears to decrease the effectiveness of oral contraceptives, might cause problems if you’re breast-feeding, and oh, right, as an herbal supplement, isn’t all that regulated. What I’m saying is, self-prescribing this stuff is not a great idea, and right now, there’s not evidence that it works for major depression. But some people do use it, so I’ll include it.

Psychiatric Diagnoses are not voodoo

The Hazards of Psychiatric Diagnosis

Read the whole thing if you want to understand my rage. Here’s the paragraph that made me stabby:

Medical diagnoses are real. When you learn you have pneumonia, diabetes or even cancer, you quickly discover that there are potential remedies. There are scientific tests and studies to diagnose the disease and to evaluate its treatment. Medical diagnoses don’t demean your mind and your soul, they describe your bodily impairments.

1) His complaint that there are no positive psychiatric diagnoses. May I ask when the last time someone was diagnosed with a most excellent spleen? People usually go to doctors because they have a perceived lower quality of life, not for validation. They get diagnosed when the doctor sees something wrong. Or are people rampantly being diagnosed with good cholesterol and no one’s telling me?

2) A diagnosis gives you something positive in that it allows you to work towards a specific goal. “I have ADD, therefore I need to take particular care to learn patience and find ways of learning that are hands on and interesting.” Instead of being like oh my life sucks and there’s nothing I can do about it you can instead be like, hey here’s what’s been wrong with me all this time and there’s something I can do about it.

3) If someone’s life sucks and getting a diagnosis is going to get them medication that will make it suck less, that’s a positive. Not everyone can look at life with sunshine and roses and hugs in their hearts, and it’s absolutely shitty of that guy to imply that people’s real problem is that they’re just not trying hard enough to face life with warm fuzzies and empathy.

4) By his definition, all drugs are toxins because the point of a drug is to try to chemically alter the body to improve symptoms. Damn those asthmatics and their toxic inhalers, how dare they want to live. Damn those depressives with their anti-depressants, how dare they want to stop being suicidal. How dare anyone take any of that voodoo medication that’s been carefully studied in clinical trials to help the symptoms these people have? Everyone knows if you treat a headache, all you are is that symptom, not some sort of human being who had a headache that needed some ibuprofen.

5) He’s just furthering the bullshit argument that psychiatric problems aren’t as “real” as other health problems. His worry that someone might be one-dimensionalized by a diagnosis is because people like him keep saying that the only important thing about a person who has been diagnosed bipolar is that they’re bipolar. As though getting a mental condition under control is going to make someone less able to live normally because they have to recognize they have issues. Yes, let’s let all the schizophrenics and autistic kids have terrible lives, but at least no one will call them schizophrenic or autistic.

6) Just to be clear, fuck that guy.