Asthma Medications

00:01 Welcome to pharmacology by Lecturio. My name is Pravin Shukle and I will guide you through respiratory pharmacology.

00:09 When we talk about drugs used in asthma, we have lots of choices. We have the bronchodilators such as the beta agonists, the methylxanthines, and the muscarinic antagonists.

00:20 We also have a choice of a number of anti-inflammatory agents including release inhibitors, slow anti-inflammatory drugs, antibody based therapies and of course steroids.

00:31 And finally, we have the new class of drugs called the leukotriene antagonists.

00:35 They can be lipooxygenase inhibitors, or they can be receptor inhibitors.

00:40 These drug classes represent the entire armamentarium in asthma.

00:45 and we're going to go over each of them in turn.

00:48 Before we do though, let's start off with principles of therapy behind asthma treatment.

00:52 An inflammed airway has thick airways and the airway itself is narrow.

00:59 So, when you take a look at a normal airway down here, you can see that the walls are not thick, and the walls are wide and open. When you take a look at a constricted airway, you can see that the walls are still the same thickness, but the entire diameter of the airway has narrowed resulting in a narrower lumen.

01:18 When you take a look at an inflammed airway, even though the walls have not constricted in, the walls themselves are thicker, so you end up with a narrower airway.

01:29 And finally, in end stage asthma, you will have a constricted and inflammed airway which results in a very narrow lumen and real illness from a clinical point of view.

01:42 So, inflammed airways, the walls are thick, airway is narrow. A constricted airway, the walls are "closed in" and the airway is narrow.

01:50 Now, treatment involves two types of therapy. You can bronchodilate or you can give anti-inflammatories to reduce thickness, or you can do both.