February 8, 2023

Clinical Cousins cover Furosemide (Lasix) in their effective and concise “Minute to Master” series.

Everyone and welcome back to clinical cuss’s youtube channel today we’re going to go over furosemide also known as lasix this drug is classified as a loop diuretic and is given for many conditions in which we need to decrease our blood volume such as edema hypertension pulmonary edema and acute hyperkalemia and hypermagnesemia and acls this is one of the most

Important drugs we will learn about because it is so effective and widely used you should not give this medication if your patient is not producing urine also use caution when giving this drug because it can cause severe fluid and electrolyte imbalances also it can even cause ototoxicity in pregnant women this drug has a category of c so use extreme caution when

Administering this drug now to make this drug so easy to understand we’re going to understand how furosemide works on a cellular level if you follow along i promise this drug will be so easy to you now here i’ve drawn a nephron and we all know that fluid is filtered and acted upon until the end result is urine now after our fluid has been filtered and acted

Upon by our proximal convoluted tubule it makes its way to the loop to the loop of henle you should know that about 25 percent of our sodium and water is absorbed by our cells in our thick ascending loop of henle normally our thick ascending cells which i have drawn one here to represent this whole section our thick ascending cells have a blood-facing side and a

Urine-facing side on the blood-facing side or basolateral side this cell has a sodium potassium atpase and a chloride channel now on the apical or urine facing side it has what is called a sodium potassium 2-chloride co-transporter also it has a leaky potassium channel normally our cell will suck the sodium it’ll suck the potassium and it’ll suck the chloride

From the urine so that we can reabsorb it into the blood at this point it means that sodium chloride and water will be entering our blood but potassium does something funny it finds a leaky channel and makes its way back out to the urine why does it do this well we know that potassium is positive so it will naturally make this space outside the cell in the urine

More positive this positive charge will actually push our positive calcium and magnesium between our cells and back into our blood this means that normally under normal conditions our cell is taking the sodium it’s taking the chloride it’s taking the water it’s taking the calcium and it’s taking the magnesium back into our blood now you will be able to tell me

What happens when we block this co-transporter with a drug like furosemide when we block this co-transporter it means that sodium it means that chloride and it means that water and potassium will be lost into our urine because potassium is lost into our urine we have nothing to make the tubule more positive this means that we will have no positive push for

Calcium and magnesium to come back into the blood this means that we will lose our free water because water follows sodium we will lose our sodium we will lose our potassium we will lose our chloride we will lose our calcium and we will lose our magnesium all because we blocked this co-transporter with a drug like furosemide now now that we understand this you

Should understand that this drug will raise uric acid levels in the blood this means that your gout patients will be more likely to have gouty arthritis flare-ups in their joints this drug has an onset of about five to thirty minutes depending on the route and it will have effects that last for two hours now the side effects of this drug may include hyperuricemia

Think out hypokalemia which means eat your fruits and vegetables polyuria hypocalcemia hypomagnesemia hypotension muscle cramps from the electrolyte imbalances and tinnitus some commonly tested material about this drug is that it is a powerful loop diuretic it will decrease our patient’s blood volume you should use caution when giving to gout patients and

It will likely result in frequent urination hypokalemia magnesemia and hypotension as always thank you for taking the time to learn with us today and remember to like and subscribe for more content

Transcribed from video
NCLEX Prep (Pharmacology): Furosemide (Lasix) By Clinical Cousins