Nitroglycerin: Drug Interactions and Tolerance – Organic Nitrates (Nursing)

00:01 Now, let's talk about not playing well with others.

00:04 There's other drug interactions that go on. We know that heart rate and hypotension are issues with nitroglycerin.

00:12 But if I already know that you have hypotension, I don't want to pair it up with other drugs that can make that worse.

00:19 So, when I think about drug-to-drug interactions with nitroglycerin, I don't want to give another drug that drops your blood pressure without really thinking it through.

00:27 Now, as we go through other experiences, we'll talk about drugs that cause hypotensive, but for right now, just keep in mind, knowing that nitroglycerin will drop your blood pressure, you want to be very careful about other medications that will also drop your blood pressure.

00:43 Yeah. Now this next one, people don't usually like to talk about, so I'm going to kind of whisper so you can -- not embarrassed. Erectile dysfunction drugs.

00:54 Men never usually want to tell us that they're on these drugs, but if they take an erectile dysfunction drug and nitroglycerin, they're going to have a really bad day.

01:06 Because erectile dysfunction drugs have really cute commercials that are kind of confusing, but it's going to cause a life-threatening drop in their blood pressure if they mix nitroglycerin and erectile dysfunction.

01:20 So, even if you're uncomfortable and your patient is uncomfortable, you've got to talk to them and ask them if they're on any erectile dysfunction drugs.

01:30 And don't say phosphodiesterase type 5 inhibitors because they likely won't know what you're talking about.

01:37 But if you use that inappropriate term, right? You know, it's not really inappropriate, just people not comfortable talking about it, ask them if they're taking any erectile dysfunction drugs.

01:48 And as men age, it becomes an issue.

01:51 If they have diabetes, it's also an issue.

01:53 If they have high blood pressure, it's a problem. So, just act like it's no big deal.

01:58 Like the first time you have to go in and cath a male, you make eye contact, you stay very calm, and you act like you talk about this all the time.

02:06 Just ask him casually. "Are you, by chance, taking any erectile dysfunction drugs?" They say "yes," they say "no," don't respond, just write it down and keep going.

02:16 If they say "yes," you're going to need to educate the patient.

02:19 Just handle it in a way that helps your patient feel comfortable, but they don't mistake the risk they're taking if they take nitroglycerin and an ED drug at the same time.

02:31 Now, with beta blockers and verapamil and diltiazem, we can use those to help deal with that heart rate issue, that tachycardia.

02:39 Remember, beta blockers and calcium channel blockers like verapamil and diltiazem will actually decrease the heart rate.

02:47 So, if the patient's really having a problem with reflex tachycardia, these are the drugs that will help.

02:52 Beta blockers will suppress that sympathetic nervous system stimulation of the heart, and verapamil and diltiazem will suppress the SA node.

02:59 So while they work different ways, they have the same effect.

03:02 Beta blockers or calcium channel blockers will cause a decreased heart rate, and that'll help us deal with that nitroglycerin-induced reflex tachycardia, meaning that superfast heart rate, > 100, that's what tachycardia is, caused by the blood pressure drop from nitroglycerin.

03:21 Now, tolerance.

03:23 In a social justice setting, that's an appropriate word, but when you're talking about nitroglycerin, it's a bad thing.

03:29 And patients can develop it really quickly.

03:31 And if I am tolerant -- building up tolerance, meaning the drug is not as effective as it used to be, to 1 type of nitroglycerin, I'm going to have a cross tolerance to all types of nitroglycerin.

03:42 Now, the higher the dose and the longer I'm on it, the higher the risk I'm at for developing tolerance.

03:47 So, to minimize the use or the impact of tolerance, we want to use the lowest effective dose for your patient.

03:54 So that takes coordination and collaboration between the healthcare team and the patient to help identify what is the minimum lowest effective dose for that patient.

04:03 So, the worst case scenario, those transdermal patches and the oral medications that are sustained release.

04:10 We can intervene with the transdermal patches by having them stay patch free, at least a minimum of 8 hours a day.

04:17 10-12 is even better if the patient can get by with that and not experience chest pain.

04:23 Okay, now, here's something that's a little different about nitroglycerin, particularly with those long- acting preparations.

04:29 We've already talked about that those long-acting preparations put us at increased risk for tolerance.

04:34 But you want to educate your patients that they will have to work with their health care provider in weaning these when it's time to discontinue them.

04:42 You do not recommend they wake up one day and say, "You know what? I'm done taking that long-acting nitroglycerin," because they're going to end up with an increased risk of vasospasms. If they don't wean that, discontinue it slowly over a period of time, they can risk vasospasms. And you know what vasospasms equal? That's right, chest pain.

05:02 So make sure you're very clear with your patients.

05:05 They need to work with their health care provider if they're no longer going to take this medication to wean it off slowly.

05:11 Because let's look at those therapeutic uses of nitroglycerin.

05:14 We can use it in acute chest pain, and you give it sublingual, translingual, and in very rare cases, IV.

05:21 In sustained anginal therapy, that's kind of over a period of time. That doesn't mean you just rolled into an ER with chest pain.

05:28 This is someone we know that has chest pain, so how do we treat that over a period of time? Could be with patches or that sustained release oral.

05:36 But again, I want you to star that right there and remind yourself, increased risk for tolerance with sustained anginal therapy, like patches and sustained release oral.

05:48 Remember, IV nitroglycerin is rarely used for acute chest pain, but we use it in surgery to help control blood pressure when we need to lower blood pressure.

05:57 We use it for heart failure or heart attack.

06:00 We use it for unstable angina if the need arises, and we can also use it for that chronic angina that we just cannot get a hold of.

06:07 But primarily, IV nitroglycerin, remember, is not a good sign for having to use it to treat angina.