Caitlin Whyte (Host): Welcome to Flourish, the podcast where we deliver expert insights and advice on health and healing. I'm your host, Caitlin Whyte. Joining us today is Dr. Alex Pyatt, a solid organ transplant pharmacist from Prisma Health. We'll discuss an important topic, protecting your kidneys from medication-induced damage.

Well, we are so glad to have you on the show today. To kick off our conversation, my first question for you is, what are the primary functions of the kidneys in the body?

Dr. Alex Pyatt: The kidneys are actually made up of about a million nephrons, which the nephron is what we consider the functional unit of the kidney, and they're designed to maintain homeostasis and balance in your body. And they do that by filtering your blood. So, they filter your blood by removing waste, and that's excreted out of your body as your urine. They also regulate blood pressure, so they can control the amount of sodium in water that's actually in your blood, and how much you actually will urinate out.

The kidneys also produce enzymes and hormones that directly regulate your blood pressure. And they also stimulate the production of red blood cells and they also activate vitamin D, which can be crucial for bone health. And overall, they also maintain your pH balance in your body. So, kidneys play a huge role in keeping balance and homeostasis with your blood pressure, electrolytes, and how your body eliminates waste.

Host: So, how do medications generally affect our kidney function?

Dr. Alex Pyatt: So, that's a really broad question. It really depends on the medication, where it works, also where it's metabolized and excreted in the body. So, I went to pharmacy school and we had years of pharmacology, pharmacokinetics, and just studying how different drugs work in your body, where they work.

So, medications can negatively affect the kidney, if part of their mechanism of action is by decreasing the blood flow into the kidney or interfering with the kidney's ability to properly function in removing that waste that I talked about, creating that urine, and filtering that waste. But it's always important to double check with a medical professional if you are worried about how a medication's working or how it may affect your kidneys.

Host: Well, let's break that big question down a bit. What about some common medications? Are there any that are known to be harmful to the kidneys?

Dr. Alex Pyatt: I think the scariest meds that can be harmful to the kidneys are the meds that you can take over-the-counter, that people just aren't aware that are affecting their kidneys. And, you know, so when a drug's prescribed by a doctor, you know, they're able to follow patients labs and make sure that their kidney function is doing okay on the meds. But, you know, when you're taking a medication that you can buy at Walgreens or CVS over-the-counter, it's important for people to know that there is a class of medications called NSAIDS, and those are like your Advil, Aleve, Motrin, ibuprofen, Goody's powders. So when you take this class of medications all the time, you know, every day, and we consider them to be high doses for long periods of time, these can actually be harmful to the kidney. And that's because they do cause decreased blood flow to the kidneys.

So, that's something to be aware of. Every once in a while for headache or aches and pains, that's okay. And sometimes people get a muscle injury and they do need to take an NSAID for, you know, a week or two and that's okay too, but it's those prolonged, chronic, every day for years where we're going to see patients that we've actually seen come in that need, you know, a kidney transplant that I've been on dialysis because of NSAID use.

There's another class of drugs that we do get asked about every once in a while and that's our PPIs, our proton pump inhibitors. Those are like pantoprazole or Protonix or omeprazole or Nexium. You might recognize some of those names that you can buy over-the-counter. These have not been proven to cause kidney failure or chronic kidney disease. Some studies suggest there's an increased risk. And then also, although it's rare, they can cause some swelling in the kidney. But in general, these are considered safe and effective. And we do use these in our post kidney transplant recipient patients without concerns.

There are many prescribed medications that can be harmful to your kidneys, especially if you have known kidney damage already. Any drug that's been FDA approved and studied has to go through trials where they look at how this drug is eliminated do we need to dose-adjust it based on patient's kidney function? And that's part of my role as a pharmacist, is to make sure that we are adjusting these prescribed medications based on patient's kidney's function if we need to.

Host: Well, who is at higher risk of medication-induced kidney damage?

Dr. Alex Pyatt: That is a broad question. That one depends. So in general, if you already have kidney problems and that you know of, and a lot of times these can be hereditary. For example, polycystic kidney disease that can run kind of in the family. So, a lot of times patients will know or go ahead and get tested and get worked up and maybe they're already following with a nephrologist to follow their kidney function as they get older.

So if you already have kidney problems, you know, you're going to be at risk for drugs just being able to cause more damage than if you had no kidney dysfunction to start with. Older age. So, kidney function actually just declines naturally with age. And then, any other comorbidities, some that come to mind are like diabetes, especially if it's not controlled. So, having high blood sugar can be really harmful to the microvasculature, those small blood vessels that are in the kidney. And then, uncontrolled hypertension. If you remember, I talked about how the kidney helps control blood pressure in your body. So, if you're constantly having a high blood pressure, that can really cause and wreak havoc in your kidneys, especially over time. So, actually, you know, people can have high blood pressure that's hereditary. It can start when you're really young, like in your 20s. You could have high blood pressure starting then and you don't even really know it. So, that'd be another reason just to follow with your primary care and get checked up on and make sure none of that's going on.

But those are the main categories that come to mind when I think of patients that are generally going to be at higher risk for medication-induced kidney damage.

Host: Well, what symptoms might indicate that a medication is affecting our kidneys?

Dr. Alex Pyatt: Any changes in urination patterns, going to the restroom, if you were ever to just stop urinating, or having reduced urinating, frequency. So, you know, maybe it burns when you urinate or you feel like you've got to go to the restroom and then you go and you don't actually have any urine; if you notice any darker than usual or foam in your urine, those can be signs that you're having some kidney dysfunction. That doesn't have to necessarily be medication-induced, but those are just signs that your kidney can give you that something's going on. Also, swelling in your legs can also be a sign of kidney dysfunction.

Host: So, how can individuals with pre-existing kidney conditions manage their medication safely?

Dr. Alex Pyatt: Yeah. So, I think the best answer to this is always check with your prescribing doctor or pharmacist. You know, there's pharmacists at Walgreens, CVS, Walmart. Always double check with them. Disclose all the meds you're taking including over-the-counter meds and supplements. There's a lot of drug interactions that can happen between supplements and herbal supplements and your prescribed medications that just probably you don't even think about that can cause unknowing kidney damage just because of the interaction that's happening.

So, I would say just always double checking with your doctor and/or pharmacist to make sure that all the medications that you're taking are okay and they're okay to take together.

Host: Well, what steps should you take if you suspect that a medication is harming your kidneys?

Dr. Alex Pyatt: Yeah. So, I would honestly just kind of lump it in with the last question of just talking to a healthcare professional, a doctor, you know, a mid level, whoever your primary care is, or if you have a nephrologist, and your pharmacist. You know, I wouldn't say necessarily to stop the medication unless it's a supplement that you're buying or over-the-counter med. But I would definitely try to get in contact with them before stopping your medication, especially, you know, if it's for your blood pressure or blood sugar or something like that, I wouldn't want you to do that, but always double check with them

Host: so, how can our healthcare providers monitor our kidney function in patients taking medications that may harm kidneys?

Dr. Alex Pyatt: I mentioned earlier that any FDA approved drug that's prescribed has been studied for its adverse effects and whether or not it can harm the kidney. They also look at whether or not it is metabolized through the kidney, if it's eliminated through the kidney, and if so, what dose adjustments need to be made based on how well someone's kidney function is.

Host: And are there alternative medications that are safer for our kidney health?

Dr. Alex Pyatt: I think it's just too broad of a question for alternative medications that are just in general safer for kidneys, and whether it's prescribed. I think that, you know, just because we have to adjust the medication that we prescribe based on your kidney function, doesn't necessarily mean that it's not safe for the kidney. We just have to make sure that it's safely used.

I will say though that for over-the-counter supplements in affecting kidney health, the FDA does not regulate herbal supplements, over-the-counter supplements for its dose, content, or pureness. There are few studies that show the benefit, and there can be a lot of drug interactions with over-the-counter meds and prescribing medications, so just re-emphasizing to make sure that those are all okay to take together.

But if you already have kidney dysfunction, you're most likely already having to limit the amount of potassium and phosphorus that you can take, especially if you're already on dialysis. National Kidney Foundation website is a great resource for the public to use, to get factual information on that.

In general, there are fat-soluble vitamins, vitamin A, E and K that can accumulate in your body and become toxic for patients that already have kidney disease. I do get asked this question a lot, especially with patients with the flu season and cold season, people ask me about vitamin C and low doses of vitamin C are fine. But when you start taking higher doses, I would say a thousand milligrams or more, it can cause a buildup of oxalate in your body and that can actually cause kidney stones. So, I would avoid that too, especially if you already have kidney disease. And then, any creatine supplements can also increase some of your kidney function that we look at. So, I would also try to avoid those as well.

Host: And are there any recent studies or advancements that have been made in understanding medication-induced kidney damage?

Dr. Alex Pyatt: There aren't really any studies like specifically just looking at this, but you know, every time that a new drug is approved or is going through the research process and the different phases, this is looked at. So, that is put under a magnifying glass and looked at how is it affecting the kidneys overall? Do we need to dose adjust it based on their renal function? So, there's always new information coming out with studies and new drugs that we're looking at, and how it affects the kidney that, a lot of times, we can extrapolate maybe to other drugs or other classes of drugs.

Host: And to wrap it up here, how do these new diabetes medications like GLP-1 receptor agonists impact kidney health?

Dr. Alex Pyatt: Yeah. So, that is a very common question that I get as well. So, GLP-1 receptor agonists, so they mimic the natural hormone in our body, GLP-1, that regulates blood sugar, promotes weight loss. And this is done by stimulating insulin release, slowing digestion, and decreasing appetite.

So, what they saw too was that GLP-1 receptor agonists have shown promise in protecting kidney function. And that's done by reducing the blood sugar levels, which helps prevent damage to the filtering units in the kidney caused by the high glucose. It can decrease protein loss through the kidneys and overall lower inflammation. 

Caitlin Whyte (Host): Well, doctor, thank you so much for this eye opening discussion on medication induced kidney damage. And if you want to learn more, you can check out our website at prismahealth. org slash flourish. And don't forget to subscribe, share, and join the conversation.

And thank you for listening.