Use the PharmacoPhoto video ‘flash-card’ series to reinforce your knowledge of drug-classes.
Thanks for joining in as we paint a drug picture of the alpha-1 adrenergic receptor antagonists praise o sin doc says o sin and other drugs that end in the osin affects our alpha one adrenergic receptor antagonists or blockers the selective adrenergic receptor blocking drugs are drugs that have a specific affinity to the alpha one adrenergic or epinephrine in united
States receptors so we are blocking the effect of adrenaline in the organs that have alpha one receptors the main organs that have alpha one receptors are the prostate and the peripheral blood vessels and therefore these drugs are primarily used in the treatment of benign prostatic hyperplasia and in the treatment of hypertension and they’re best placed in people
Who have both conditions simultaneously let’s take a look at these drugs a little bit closer the alpha one receptors are located primarily in these smooth muscle receptors of the prostate and in the smooth muscle receptors of the peripheral blood vessels by saying peripheral blood vessels we mean the blood vessels to the skin the extremities and the peripheral
Organs including the gi t in a fight-or-flight response adrenaline or epinephrine in the united states binds to the muscles of the blood vessels and constricts them we do that because we need to run away this is a fight-or-flight rhys and we’re closing off the blood to the periphery so that we save the blood for the big muscles that are going to be used to run
Away and for the heart the lungs and the brain so praise o sin doc says o sin and other osin medications dilate the peripheral blood vessels resulting in not only the desired effect of decreased blood pressure but it can also result in hypotension orthostatic hypotension headaches nasal congestion and dizziness now all of that is from the dilation of the blood
Vessels it’s probably a good idea for you to note at this point that there are some third-generation alpha-1 blocking agents that have a greater affinity for the very very selective alpha one a receptor that’s on the prostate versus the alpha 1b receptor on the blood vessels so those agents include alf fuse o sin and tamsulosin and those wouldn’t have as much of
An effect on the blood vessels and therefore they won’t have as many of the side effects that are associated with the blood vessels also in a fight-or-flight response we tighten up the muscles around the urinary system because we need to flee not p benign prostatic hyperplasia is a disorder that becomes increasingly common in men as they age the prostate completely
Surrounds the urethra in males and as the men get older the effects of testosterone oftentimes increase the size of all the cells or nearly all the cells of the prostate and that makes it a lot more difficult to urinate if benign prostatic hyperplasia remains untreated the fluid can actually build up in the structures above the prostate and that can damage not only
The urinary bladder but it can damage and even destroy the kidneys antagonizing or blocking the alpha-1 receptors does not shrink the prostate for instance but it actually leads to a relaxation of the smooth muscles of the prostate and the urinary sphincter and that decreases the resistance meanwhile this action may actually cause urinary incontinence in people with
No urethral obstruction praise our sin duck says oh sin and other drugs that end in the osi and effects are not the first-line treatment for hypertension or for benign prostatic hyperplasia but they are a drug that can be considered for other condition and especially if the person has both conditions simultaneously orthostatic hypotension is a condition in which
There is a fairly large fall in the blood pressure as a person gets up from a seated or a lying down position and syncope is a condition where the person actually faints due to a lack of blood that going going to the brain and either of those conditions can occur with praise of sin and dox a zosyn so it’s important to instruct the person taking those medications
To get up very very slowly to get their balance before they start moving you
Transcribed from video
Alpha blockers: Prazosin, doxazosin, alfuzosin, tamsulosin (…osin drugs) By PharmacoPhoto