The 'Triple Threat' Caused by Blood Pressure Medication and Over-the-Counter Painkillers, and How to Prevent It

Loxonin, of which approximately 600 million tablets are consumed annually in Japan.

When you visited your parents' home,
didn't you see a familiar box just sitting on the living room table or in the medicine cabinet?

“My knees have been hurting lately,” or “I’m prone to headaches.”
Over-the-counter painkillers that parents have been using for years because they can be bought without a prescription and are effective.

You might not think of them as 'dangerous drugs' at all.

However, what if that one pill your parent is taking so casually is quietly destroying their kidneys?

This is not a story about 'being careful not to take too much medicine.'

It is a story about elderly parents who diligently take their prescribed medication for chronic conditions,
unknowingly damaging their own kidneys.
I want to deliver this information to you, living apart from them, today.

The 'over-the-counter drug' that appeared from a drawstring bag one day

There is an unforgettable scene that became the catalyst for me to focus on the kidneys.

A patient suddenly fell ill and was hospitalized.
The test results showedacute kidney injury.
Their kidney function had dropped rapidly.

They had been receiving prescriptions from their family doctor for many years,
and three types of medication were recorded in their medication notebook.

Two types of blood pressure medication (an ARB and a diuretic),
and a cholesterol-lowering drug.
All were carefully managed, problem-free prescriptions.

Just as I was checking the medications one by one.

From a small drawstring bag among their belongings—an over-the-counter painkiller appeared.

“Ah, this is it...”

I didn't say it out loud.
But I felt a heaviness deep in my chest.

Because it was an over-the-counter drug, because it didn't require a prescription,
perhaps they never thought of it as 'medicine.'
Perhaps they had been taking it casually whenever they felt pain.
Perhaps they were just trying to manage the pain themselves.

If only their family living apart had known about this combination—.
That regret is what led me to focus on the kidneys,
and it is the reason I am writing this article.

From my position as a specialist in renal pharmacotherapy,
today I will provide you withinformation that 'could have been prevented if known',as specifically as possible.

First of all, what are 'NSAIDs'?

'NSAIDs' is pronounced 'en-saids'.
In Japanese, they are called non-steroidal anti-inflammatory drugs.
It is a difficult name, but
in short, it refers to a 'group of drugs that suppress pain and inflammation'.

Many of the painkillers that can be easily bought at drugstores
are classified as these NSAIDs.

To list some representative examples—

One thing to be careful about is
not to judge solely by the brand name 'Bufferin'.

The Bufferin series has multiple products,
and they contain completely different main ingredients.

The main ingredient of 'Bufferin A' is aspirin, but
'Bufferin Premium' is a combination drug of acetaminophen and ibuprofen.

Even with the same brand name, the contents can be completely different drugs.
There are also products like 'Naron Ace T' that contain a mixture of NSAIDs and acetaminophen.

Always check the 'ingredients' listed on the back.
The habit of judging by ingredient name rather than brand name
will protect you, the reader, and your parents.

'It's not an oral medication, so it's safe' is a big misunderstanding—the pitfalls of patches and poultices

'Because it's not an oral medication,'
'because it doesn't pass through the stomach or kidneys,'
don't you feel 'safe'?

It is true that common over-the-counter poultices and topical medications
have a much smaller amount entering the body compared to oral medications,
and in many cases, they are a safe option to use.

However,
the idea that 'because it's a patch, it has nothing to do with the kidneys' or 'it's fine to apply as much as you want'
is unfortunately a misunderstanding
.

Ingredients like those in Loxonin Tape or Voltaren Gel
are also absorbed through the skin, albeit in small amounts, and enter the bloodstream to circulate throughout the body.

If you apply too many at once because you are in pain,
or use them continuously for weeks,
more ingredients than you might think will circulate in your body,
which can increase the burden on your kidneys.

Furthermore, among the patches prescribed by medical institutions,
some have ingredients that enter the bloodstream in amounts close to oral medications.

Representative examples include Rocoa Tape and Zictor Tape,
and for those whose kidney function is significantly reduced,
rules such as 'must not be used (contraindicated)' or 'use with caution'
are specified in the package insert.
(However, it is necessary to check as the latest information may be updated.)

The common knowledge that 'it's just a topical or patch, so it's unrelated to the kidneys'
should be rewritten starting today.

Especially for parents who have kidney disease or
are taking blood pressure medication or diuretics,
it is safer to consult a doctor or pharmacist before using not only oral medications but also patches and topical medications.

Why do NSAIDs damage the kidneys?

Understanding the mechanism will help you realize 'why it is dangerous.'
I will not use technical jargon, so please read on.

The kidneys are organs that 'filter' blood to produce urine .
To perform this filtration,
a constant amount of blood must flow into the kidneys.

Our bodies have a mechanism that automatically regulates blood flow to the kidneys.
Prostaglandins are substances that act as the 'faucet' ,
adjusting the flow to ensure enough blood reaches the kidneys.

On the other hand, prostaglandins are also substances related to pain.
NSAIDs relieve pain by suppressing the production of these prostaglandins.

In other words, while they eliminate pain, they also close the kidney's 'faucet' .

When healthy people use them in appropriate amounts under appropriate circumstances,
the body covers for it well.
The problem arises when the following 'multiplication' occurs .

The 'dangerous multiplication' with dehydration

In these states, blood flow to the kidneys is already reduced.
When NSAIDs are added to this, the faucet is tightened further, and
the kidneys temporarily fall into a state of 'water shortage' .

This contributes to a condition called acute kidney injury (AKI).
A single instance of severe damage
can reduce kidney function to a point where it cannot recover.
Even if you regret it later, thinking 'it might have been because I took that,'
it may be impossible to go back.

Things to check if you are taking blood pressure medication

As of 2017, it is estimated that
there are approximately 43 million patients with hypertension in Japan.
This means that more than one in three Japanese people fall into this category.
Even if you think 'my parents are different,' please check once.

In the treatment of hypertension, the following types of drugs are sometimes used.

• ARBs/ACE inhibitors (representative drugs for lowering blood pressure)

• Diuretics (drugs that excrete excess water from the body)

It is known that when people taking these drugs add NSAIDs,
the burden on the kidneys increases not by 'addition' but by 'multiplication'
.

In the medical world, this combination is called
the 'triple whammy,' and it is
a combination to be careful of because it increases the risk of acute kidney injury.

You don't need to memorize it, but
please be aware that 'this combination has a dangerous enough reputation to have a name.'

In the episode at the beginning, what came out of the patient's luggage
was exactly this situation.
A combination of an ARB and a diuretic, with an over-the-counter painkiller added.

The judgment that 'a little bit is fine' is the most dangerous judgment of all.

Do you think, 'My parents are not affected'?

The reason kidney damage caused by NSAIDs is so terrifying is that
the kidneys are organs that do not feel pain.

If your stomach is irritated, you feel discomfort.
If your liver is damaged, you may experience fatigue or jaundice.
However, even when kidney function drops below half,
in most cases, there are no subjective symptoms at all.

By the time you notice, chronic kidney disease (CKD) has already progressed
—such cases are by no means rare.

They look healthy, have no underlying conditions, and have never had issues in health checkups.
Even so, the kidney is an organ you cannot be complacent about.
The assumption that 'my parents are fine' is the most dangerous thing for that reason.

Let's change our actions starting today—steps you (the child generation) should take

I will explain the specific actions you should take by dividing your parents' situations into two patterns.

【Pattern A】 Parents taking medication for blood pressure, heart conditions, or swelling (diuretics)

This is the highest-risk group.

STEP 1: Check the medicine cabinet when visiting home

First, please casually check the medicine cabinet, drawers, or the top of the table. If you find any of the following, be careful.

It is dangerous to judge based on the brand name alone.
Always check the 'ingredients' section on the back.
If you see the words 'ibuprofen,' 'loxoprofen,' 'aspirin,'
or 'diclofenac,' it is an NSAID.

STEP 2: Talk to your parents

Even if you find them, telling them 'Don't take that!' outright is counterproductive.
The parent generation may feel that 'a medicine I've used for years is suddenly being rejected,'
and they may stop listening to you.

This way of speaking is easier to get across:

There are three points.

Instead of saying 'You are wrong,' use a tone of 'Let's check together.' Borrow the words of a third party by saying 'The pharmacist said so.' Instead of saying 'Stop,' lower the hurdle for action by saying
'Please check it.'

STEP 3: Accompany them to their next doctor's visit or pharmacy (or consult on their behalf by phone)

If it is difficult for your parent to explain the situation to a doctor or pharmacist alone,
you can accompany them or consult on their behalf over the phone.

What to say at the counter (you can use this as is):

This is all you need to say.
The pharmacist or doctor will handle the rest.
If it is the hospital that issued the prescription,
“Please prescribe a safe painkiller that can be used as needed”
is also an effective request.

[Pattern B] Parents (or yourself) who have no underlying conditions but use over-the-counter painkillers for fatigue, colds, etc.

This pattern involves the largest number of people,
and the misconception that “I am safe” is common in this group.

It is not completely without danger.

In particular, please avoid using NSAIDs in the following situations as much as possible.

These are all situations that lead to a risk of dehydration. The guideline for action when these situations apply is
2 steps.

Step 1: First, drink 1 to 2 glasses of water.
Relieving dehydration even slightly is the first step.

Step 2: If you still have pain, consider acetaminophen as the first choice.
“Tylenol A” and similar products can be purchased as over-the-counter acetaminophen medications.
Because they have less of an effect on directly reducing blood flow to the kidneys than NSAIDs,
they are suitable for use in situations with a risk of dehydration, as shown in the table above.

However, there is an important caveat here.

⚠️ Acetaminophen is “better than NSAIDs,” but it is not “completely safe.”

For those who already have reduced kidney function—those who have been told they have abnormal eGFR or creatinine levels in health checkups—there is also a risk with acetaminophen if used in high doses or over a long period.

Taking the information that it is “kinder to the kidneys than NSAIDs” at face value
and continuing to make decisions on your own has its limits.

Finally: The kidneys cannot speak. So, please be the one to notice.

Those who have read this far will likely no longer overlook
“the Loxonin in their parents' medicine box” with the same mindset as before.

Let's summarize what we have covered today.

I still remember that feeling
the moment I saw the painkillers that came out of that drawstring bag.

It might have been preventable.
Every time I think that, I feel I should have delivered this information sooner.
But today, it has reached you.
That alone makes writing this worthwhile.

This is not just about NSAIDs.
The relationship between the kidneys and medication extends to all kinds of drugs, including contrast agents, antibiotics, and certain herbal medicines.
Using medication safely is deeper than you might think,
and it requires more daily care than you might imagine.

What I have shared today is truly just the beginning.

But if you switch your painkillers to acetaminophen,
will that protect your kidneys?
Unfortunately, the answer is no.

This is because many people make the
fatal mistake of thinking that because their 'creatinine' levels in their health checkup are normal, they are fine.

For elderly individuals with reduced muscle mass, it is not uncommon for actual kidney function to be impaired even if blood test results appear 'normal'.

What do we, as pharmacists on the front lines, look for to determine the true risks hidden behind those numbers?

If you find yourself wanting to know more about kidneys and medication,
please follow this note.
For those supporting CKD patients or elderly family members,
I will continue to share the 'criteria that pharmacists actually use in practice' in a concrete way.

The kidneys are a silent organ.
That is why you, as a family member, need to speak up on their behalf.

▶ Sequel: Why you should not trust 'creatinine is normal'

▶ The issue of supplement interactions for patients with weakened kidneys