Pharmacodynamics: Understanding the Basic Terms (Nursing)

00:00 Hi.

00:01 Welcome to our video on pharmacodynamics.

00:04 Now, you might be asking yourself, “Why in the world do I need to know about pharmacodynamics?” Well, it’s actually a really cool part of pharmacology.

00:12 So, let’s walk through how this is going to benefit you as a practicing nurse to understand these really important concepts.

00:18 Okay, so if you understand how pharmacodynamics work, remember we’ve discussed pharmacokinetics, that’s how the body moves the drug all the way through.

00:28 Pharmacodynamics is how the drug impacts the body, so it’s really important that nurses understand that plus all the individual patient variations.

00:37 Okay, so when you understand pharmacodynamics, you can advocate effectively and that is your main role at the bedside.

00:44 Our job is to advocate for the patients: to make sure they get the right medications, they get them safely, and they’re effectively doing what the healthcare provider wants them to do.

00:53 It helps you make safe decisions about your medication.

00:56 If I’m taking a medication, I want to make sure it’s the safest choice for me and I want the same thing for my patients, and I know that you will too.

01:03 Now, in order for me to assess the medication, I need to share all that information with the patient and what they need to know to be safe at home too.

01:10 So, I’ll use it to help educate the patients about their medications.

01:14 So, it’s all about me being a safe practitioner and helping the patient carry that same safe practice into their home setting.

01:22 So, let’s start with some basic pharmacodynamic terms.

01:26 Now, the first one is a tongue twister, so I’m going to say it very slowly— maximal efficacy—there, I did it.

01:33 Now, let’s talk about what it is.

01:35 It’s the biggest effect a drug can have on the body.

01:38 That is much easier to say and to understand.

01:41 So, we’re looking for a big effect of a drug that’ll have on the body. Remember, pharmacodynamics is the effect of the drug on the body.

01:51 Now, potent drug, that’s easier to say, but we’re talking if it’s a potent drug that means that it produces an effect at a relatively lower dosage.

02:00 Let me give you an example.

02:01 Morphine is a drug that we use for pain control.

02:05 Most everybody is familiar with what that name is, but fentanyl also is used for pain control and it’s a much more potent drug, 100 times more potent.

02:16 So, that’s what we mean when we talk about a drug’s potency.

02:19 There may be 2 drugs that do similar things but 1 is much stronger or potent.

02:26 The next term is receptor binding.

02:28 We’ll talk more about receptors as we move through this presentation, but we just want to introduce you to the concept that receptors are special proteins that other substance bind to.

02:39 Now the last term on this slide is affinity, and that’s just the strength of the attraction.

02:44 Once the molecules are bound together, how strong is that bond? Okay, so those are just 4 basic terms that you should understand in the beginning of pharmacodynamics.