Biguanides – Oral Antidiabetic Medications (Nursing)

00:01 Okay.

00:02 So, let's go back and look at each one of the families.

00:05 First group, biguanides.

00:07 Now, an example of a drug in this family is metformin.

00:11 This drug is -- you'll see it everywhere.

00:15 If you've been in the clinical setting yet, I can almost guarantee you've taken care of somebody on metformin.

00:21 Now let's look at how it works.

00:23 It increases the glucose uptake by the muscles, and it decreases the glucose production by the liver.

00:29 That's why you end up with a lower blood sugar.

00:31 It helps those muscles take up extra glucose, and it'll tell the liver, "Hey, hey, don't make any more glucose.” That's what gives us a lower blood sugar.

00:42 Now, some of the problems with metformin, particularly when you start it, it has some GI distress.

00:48 You can also have some rare metabolic acidosis with renal impairment, but predominantly what people are going to see is the GI distress.

00:56 This is another one of those medications that you do not want to drink alcohol with, and we'll go into that in a little more detail.

01:04 So we know that this medication is commonly the first type of medication prescribed for a new type 2 diabetic.

01:11 It used to be that we would try lifestyle first, and do not get me wrong, lifestyle has a huge impact on type 2 diabetes.

01:19 Staying active and eating healthy, there's a phenomenal benefit for that.

01:24 In fact, if you really want to delay the progression of diabetes, you want to be serious about your lifestyle change.

01:31 So we found that when a patient is first diagnosed as being diabetic or even pre-diabetic, we're starting to now prescribe metformin right out of the shoot to kind of help give them that extra boost and lowering their blood glucose, while they're working on their lifestyle.

01:47 All of us know that's never an easy choice to make, but I promise you, this particular disease is phenomenally impacted if you can help a patient be more active and make healthier choices.

02:00 Now, metformin may be used by itself, which is considered monotherapy, meaning one therapy, or it can be used in combination with other medications.

02:09 That'll be determined by the healthcare provider and how the patient is responding.

02:14 So, metformin is okay to be used by itself.

02:17 Some of these other ones have to be used in combination.

02:20 But this drug -- So I want to make sure you have that point clear.

02:24 Metformin is okay to be used by itself and used in combination with other medications.

02:30 Now, there's also some new research coming out that this may become a drug of choice for people with gestational diabetes.

02:37 Gestational diabetes means a woman who is pregnant who develops high blood sugars during the pregnancy.

02:43 Sad part about this is if you develop gestational diabetes, you're at a higher risk to develop type 2 diabetes.

02:50 And it hasn't become practice yet.

02:52 Normally, we use insulin to try and deal with a gestational diabetic client's blood sugar.

02:57 But metformin is showing promise, so this may be something that you see in the future.

03:04 Now, this is serious, and again, I love the graphic here.

03:08 Bam! There is a punch to the kidneys to help you remember, people with metformin, if they take it with cimetidine, we've got a risk for lactic acidosis Brutal on your kidneys.

03:21 So, if someone is taking metformin, they cannot take the other medication, cimetidine, okay? That's an H2 antagonist.

03:29 We can give them another H2 antagonist that blocks stomach acid for people that have peptic ulcer disease, but they cannot do cimetidine and metformin because it gives them increased risk of lactic acidosis.

03:43 So make sure you underline lactic acidosis.

03:47 And remember, don't miss that boom, that punch to the kidneys.

03:51 That's a great reminder of the damage it can do to your kidneys.

03:55 Remember we said don't drink alcohol and take metformin? That's again -- bam! That's a punch to the kidneys.

04:04 Also, here's another very important point.

04:08 If your patient has a test that involves an iodine based radiocontrast dye, we do lots of these tests with dye.

04:16 If they're allergic to shellfish -- whoo, that's going to be a problem because they'll have an allergic reaction to the iodine-based dye.

04:23 But if you have this test and the patient's taking metformin, we've got a definite problem.

04:29 That metformin needs to be discontinued.

04:32 You see, DC there? That means discontinue the metformin 1-2 days before the test and for 48 hours afterwards.

04:41 And you don't want to restart the metformin until you make sure that the kidney function is at baseline.

04:47 So, it's critically important whenever you have a patient who's taking a test with radiocontrast dye, some type of X-ray or CAT scan that's going on, make sure you assess them for being on metformin because we're going to have to do something else to manage their blood sugar for about 4 or 5 days.

05:07 Now let's talk about what the early signs are of lactic acidosis because that's when you want to catch it.

05:12 Also, you want to teach your patients that are on metformin what these signs are.

05:17 So, they might have some unusual sleepiness or drowsiness.

05:22 They'll have a hyperventilation, and if you watch our ABG video, we'll go into more detail.

05:27 But when you're acidotic, think of CO2 in your blood as an acid, and your body tries to hyperventilate to -- blow off all that CO2 to bring your pH back more down to normal.

05:41 So, they'll be unusually sleepy or drowsy, they'll try to blow off that extra CO2 to bring the pH back to normal, they might have myalgia and muscle pain, so you want to watch your patient for these signs.

05:55 Well, what do we do if this happens? Well, we want them to contact their healthcare provider immediately.

06:01 What we'll end up doing, likely, is to stop the metformin, of course, and if it's really bad and out of control, the patient may have to have dialysis.

06:09 So, we'd like to catch it before it gets to that point, so you want to educate your patient to look for 3 main symptoms: kind of sleepy or drowsy, notice that they're breathing faster, or if they're starting to have those myalgia muscle pains.