Postganglionic Sympathetic Nerve Terminal Blockers and Monoamine Oxidase Inhibitors – Drugs in Hypertension

00:01 Let's move on to the postganglionic sympathetic nerve terminal blockers.

00:06 Now, reserpine is the prototypical drug in this class. It depletes norepinephrine from nerve terminals.

00:13 I discussed this drug in the autonomic nervous system lecture previously.

00:21 Guanethidine is another agent that depletes norepinephrine from the nerve terminals, and it also has some activity in blocking its release.

00:30 Now, I want to have a bit of a controversial statement here.

00:34 These drugs have frequent side effects. They are not very effective and they are just not used in clinical practice.

00:40 Doctors who treat hypertension hate these drugs. I have a very large hypertension practice, I have not used reserpine in probably ten years. We rarely think about these medications.

00:52 Pharmacologists love these drugs, and always put them on your exams.

00:57 So, you need to know these drugs, even though none of your clinical teachers know them, because they are going to be on your exams whether we use them or not.

01:08 Monoamine oxidase inhibitors actually do have some blood pressure activity.

01:13 Remember that MAOs cause a false transmitter. They do cause lowering of blood pressure.

01:21 In fact, even in patients who are using monoamine oxidase inhibitors for depression will have reduction in blood pressure.

01:30 In fact, if you take a look at your psychiatric medication lecture and today's lecture, you'll see that I stole this image from the psychiatry lecture.

01:41 Now, one of the things that I mentioned to you before in the psychiatry lecture is, foods high in Tyramine like cheese and wine can cause a release of a large amount of noradrenaline or norepinephrine.

01:53 And this can cause a large increase in blood pressure.

01:56 Have a look at that other lecture in antidepressants and you can see how that works.

02:03 Now, these drugs have frequent side effects. They are not very effective and as I said before, they are not used a lot.

02:09 Once again, doctors hate these drugs for hypertension and never think about it, but pharmacologists love these drugs and put them on exams in the hypertension section.

02:19 I'm not going to say that about its used in depression, because in depression, we do use them more than we do in hypertension.