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.