 Welcome to Nursing School Explained and this video on the peak and trough of a medication which helps us to understand how the individual patient is metabolizing a certain medication and drugs that come to mind here are the medications in the antibiotic group ending in mysins such as Gentamiasin, Vencomiasin, Tobramiasin all of those because they can be toxic to the kidneys if the patient is not excreting them appropriately. So for peak and trough here first of all it helps us determine if the medication is within the therapeutic window because if we have too little or too much of an effect, that's not good for the patient either and peak and trough is the blood testing of the medication in the patient's body peak meaning that we are measuring the drug concentration at the time of the highest level of the patient in the medication bloodstream and that is very similar to the time arranges that we typically reassess our patients for medication side effects. So for IV administration it would be 15 to 30 minutes after the infusion is completed for IM 30 to 60 minutes after and for PO about one hour after. So as nurses it's our responsibility to coordinate the blood draw at those specific times so that we can make sure we have the exact measure at the peak time of the patients in the of the medication in the patient's bloodstream. And then trough is the other end of the spectrum which is the lowest level of the medication in the patient's blood which is tested right before the next dose is given so when the medication is at the lowest level and then over here this is a graph that also relates to the therapeutic window and please watch a separate video about that and so this graph here represents the drug concentration and then over here over time and the lines in black are the medication administration, how it amps up and then is broken down again depending on the patient's kidneys liver as well as the half-life of the medication and then we give the next dose because typically these are antibiotics that we measure and they take another curve. And please look at the videos about steady-state and half-life so that you can relate to this topic as well. Now if the drug concentration is too little we might not have any effect, but if it's too much the patient might be experiencing toxic effects of the medication. But in between where we have the therapeutic window here the peak of the medication is when the peak has been reached and then the trough again is the lowest concentration of the medication which is not here at the X axis but it is actually when these two when the last medication overlaps and then the next one is given again because the medication does not a hundred percent get metabolized out of the patient system because we want to achieve the steady-state to get into the therapeutic window. So hopefully this helps you distinguish between peak and trough and help you understand that a little bit better and know that we mostly use this for antibiotics that can be nephrotoxic because we always worry about the patient's kidneys and how certain medications could affect their kidney function. Thanks for watching this video. Also check out the other videos in the pharmacology as well as the laboratory testing playlist so that you can get a better understanding and see how they all relate to one another. Thanks for watching. See you soon.