Overview – Antidepressants

00:01 Hi, welcome to pharmacology by Lecturio. My name is Dr. PJ Shukle and we are going to cover an important topic today, the antidepressants. Depression is a disease with a mortality. Robin Williams, Kurt Cobain, Whitney Houston and Marilyn Monroe all suffered from various levels of depression. If anybody tells you that depression isn't an important disease, they are wrong because depression has a mortality associated with it. And the tragic thing about depression is that we can't treat it. Let's take a look at the drugs that are currently used for depression. We have the monoamine oxidase inhibitors. These are the first drugs that we ever used in depression. Tricyclic antidepressants and heterocyclic andtidepressants follow. The heterocyclic antidepressants are divided into three categories. The serotonin- norepinephrine reuptake inhibitors or the SNRI's. And the serotonin receptor antagonist or the SRA's. There are other classes as well. And finally the new serotonin specific or selective serotonin reuptake inhibitors or the SSRI's.

01:16 These are the most commonly used now because they have the best side effect profile. Now there is a problem with this classification. It's technically correct but it's no longer used in practice or even in some textbooks. So what we do now is we just give them each their own category and that's how we are going to approach this sets of lectures. Let's start off with the amine hypothesis of depression. Depression is the result of low levels of amines in the synaptic cleft.

01:46 Those amines can be serotonin or can be norepinephrine. So here we have a schematic of either a norepinephrine neuron or a serotonin neuron acting on a post-synaptic neuron. What I've done here is I've given you examples how each of these drugs work. And we are going to cover each of them individually.