Hypothyroidism: Treatment with Levothyroxine (Nursing)

00:01 Let's take a look at levothyroxine as a treatment for hypothyroidism.

00:06 And I also want to break down the mechanism of action well for clients that don't have enough thyroid hormone.

00:11 Fortunately, we've had some form of levothyroxine or T4 since the late 1920s. Now, this levothyroxine can serve as a replacement for what the body can't seem to make or its endogenous thyroid hormones of T4. So the synthetic hormone that's what levothyroxine is will replace the body's thyroxine level if the thyroid gland can't produce it.

00:35 So this medication levothyroxine will mitigate the symptoms of hypothyroidism. So since the body can't make it this drug, the synthetic form of the drug of levothyroxine, will help the body have enough available T4.

00:50 Now, the levothyroxine will start working right away, but it might be several weeks before the client starts to see an improvement in their symptoms. So let's break down that MOA just a little bit more on how this synthetic hormone or levothyroxine treats hypothyroidism.

01:08 Obviously, since the client has hypothyroidism, they don't have enough T4 available in their body.

01:14 So when we replace that with this synthetic hormone now we're going to raise that level of T4. Now that means the body's going to be able to take that T4. And in the peripheral tissues it's going to turn it into T3. Now that's a good thing because that's going to regulate their cellular metabolism.

01:32 It'll impact their growth and development.

01:34 And it also goes after protein fat and carb metabolism.

01:38 So when the client's body can't make enough of the thyroid hormones, we replace it with the synthetic hormone levothyroxine.

01:46 So I want you to have this special note though.

01:49 Primary hyperthyroid cases require only T4 replacement.

01:53 Now think about that. Why would primary have a different treatment plan than secondary? Well, primary just needs T4 because the thyroid gland isn't producing enough T4. But secondary cases have another problem and they may require additional hormone replacements.

02:11 That's why it's critically important that you understand the difference between primary and secondary hypothyroidism.

02:19 In regards to the treatment for hypothyroidism, there are key things you need to know about monitoring, assessment and lifespan concerns.

02:27 So the monitoring parameters are going to differ.

02:29 Right for primary TSH is a fairly reliable marker for treatment.

02:34 For secondar. You need to look at free T4 to use that as a monitor for therapy, so keep that in mind that you're going to be looking at different lab values.

02:43 Now, how you titrate each dose varies with each patient and whether it's primary or secondary. Also, keep in mind the patient's prognosis and complications will also differ by patient and by diagnosis.

02:56 So think about pediatric patients.

02:58 Let's start with a lifespan concern.

03:00 Consider that the medications are critical for growth and development.

03:05 This is obviously a much bigger issue in pediatric clients.

03:09 Now doses are based on weight and on age.

03:12 And a pediatric client is going to need very frequent monitoring to make sure everything is on task.

03:19 Now, for older patients, they have potentially compromised organ function. So you're going to see that their doses will start lower, they'll have gradual dose increases and they'll also have increased monitoring for cardiovascular effects.

03:33 So just like anything else, our fragile populations of pediatrics and our older clients need closer monitoring.

03:40 Now for TSH monitoring every 6 to 8 weeks is what is monitored until the client is stable. You also look at free T4 levels.

03:48 You also want to make sure that you have a regular monitoring of the lipid profile, a CBC, and a full metabolic panel.

03:56 Now there are some adverse effects, and even a black box warning for patients who are being treated for hypothyroidism.

04:02 Now, the common things that you're going to hear you think about when we're giving them replacement of thyroid hormones, everything's going to be revved up.

04:10 So when they're not receiving medication, remember they're tired.

04:14 Their heart rate is slow.

04:16 When they are receiving medication they replaced with synthetic hormones.

04:20 They could have heart palpitations.

04:22 They might be anxious.

04:23 They might have tremors, it might not be able to sleep. And the opposite here is they cannot handle heat, small amount of heat.

04:30 And it really is bothersome to them.

04:32 So it's the exact opposite of their symptoms of hypothyroidism. Now remember with lifespan parameters, particularly with our elderly clients, you're watching for cardiac dysrhythmias.

04:44 Now that is a severe adverse effect.

04:46 But they may have cardiac dysrhythmias, angina, chest pain or even a thyroid storm.

04:52 Now a thyroid storm is rare, but just keep it in mind that that is a possibility. So the common ones they may notice their heart feels like it's kind of racing. They may feel more anxious.

05:03 They may have some more tremors, difficulty sleeping.

05:05 Those are not life threatening things, but they are a quality of life thing.

05:09 But the severe ones are the ones that would need immediate response.

05:13 So cardiac dysrhythmias, chest pain or the most rare thyroid storm.

05:18 Now there is a little bit of controversy with levothyroxine.

05:22 This medication has been shown to increase metabolism, which means some patients have wanted to misuse this medication in order to lose weight. Well, the Food and Drug Administration has placed a black box warning on levothyroxine, indicating that it should not be used for weight loss to treat obesity.

05:40 You're very likely to have a patient with hypothyroidism, so I want to go over the most important points for patient education.

05:48 Now first of all, this is one of those medications that really needs to be taken at a consistent daily time.

05:55 So talk with your patients, see what fits with their schedule, help them set an appropriate time that they think they can stick to.

06:02 Now they're going to also need regular monitoring and dose adjustments, so remind them of how important it is for them to come and get their lab work drawn.

06:10 When you need that information.

06:11 They also need to know this is not a medication that you should skip or you should not double the dose. So if they miss a medication, make sure that you're very clear on what the individual plan is for that client.

06:23 Now, the rest of this gets a little sticky, right? Because you need to take the medication on an empty stomach to get the maximum absorption, which means we'll get the maximum result from the medication.

06:34 But there's this four hour problem, right? You shouldn't take this medication levothyroxine within four hours of other medications or food.

06:44 So you can see the patient's going to need to be really precise about when they think the right time in their day would be to take this medication.

06:52 So when they take it, they should not have any food on their stomach. They shouldn't take it with other medications, and they shouldn't use calcium, iron or other mineral supplements within four hours of the medication.

07:05 Well, that wraps up the most important things.

07:09 Remember, these medications are powerful.

07:11 Now, some primary care providers will even recommend that the patient is under the supervision of an endocrinologist.

07:17 Someone who is a specialist in the endocrine system.

07:20 Also, remind them one last thing that consistent and good hydration is critically important.