HOME CONTACT ADVERTISE
    
 
World Doctors Directory -World's largest resources of General Practitioner, Dentist, Cosmetologist, Optician, physical Therapist, Family Therapist, Veterinarian databases
Extended Reading.....
Your Kidney Function Really Matters: A Lighter Look at What You Need to Know to Prevent Adverse Drugs

Kidney FunctionWhen you (or loved ones) are taking prescription or over the counter medications...there is a lot you should be worried about, and a lot that your pharmacist may not be telling you.

Most people are aware, for example, that several medications taken together can sometimes cause harmful interactions. Most also know that drug allergies can pose significant hazards. (These are topics of other articles in this series). And, many people know that young children, elderly adults, pregnant women, nursing women, and severely debilitated people may all be at higher risk for adverse drug events.

But what most people don't know is that a simple blood test can be one of the most important pieces of information in determining the correct dose of many medications...and the results of that test are almost never available to your pharmacist, especially if your pharmacist fills your prescription in a retail drugstore. (And, that's a bummer.)

The test I'm talking about, of course, is the 'serum creatinine test' ('SEAR-'em cree-AT-tuh-neen tehst'. It's a difficult name to pronounce and a difficult test to understand...but one that you NEED to know about if you or loved ones are taking over-the-counter or prescription medications.)

A serum creatinine test gives a physician or pharmacist an estimate of kidney function.

Serum creatinine is the 'bean counter' of modern medicine... letting folks know if the beans (the kidneys) are working as well as they should.

Why is that important?

Well, kidney function is extremely important in determining the correct doses of many medications since the kidneys (along with the liver) assist in the removal of medications from the body.

Almost all medications (and/or their chemical by-products) are either removed by the liver, by the kidneys, or, in many cases, by both the kidneys and liver working together.

So, simply put, when the beans are not working well, many medications will accumulate in the body and increase the risk of drug side effects. And that's an even bigger bummer. (The same is true for liver problems, and we will talk about that in another article in this series.)

As a result, patients with reduced kidney function often need LOWER doses of many medications.

So how does this all work?

Well, creatinine is a chemical that occurs and circulates naturally in the human body. It is the result of normal protein break-down. And, like many medications, creatinine is normally removed from the blood by the beans. So, when the kidneys are not working well, the level of creatinine circulating in the bloodstream will start to go up...just like the blood level of many medications.

Physicians and pharmacists are routinely and easily able to determine how much creatinine is in the blood with the results of a serum creatinine test. (This test is part of a very common panel of blood tests. And, if the serum creatinine is high, many drugs need to have a lower dose.) The normal value for serum creatinine is about 0.4 to 1.5 mg/dl...but that can vary a bit from lab to lab.

So remember: 'kidneys no work...serum creatinine go UP'.

Now, serum creatinine is not the best measure of kidney function (there are other tests that are much more accurate), but results of the serum creatinine test are usually the most readily available...and cheapest...and are generally accurate enough for most purposes...so serum creatinine is the de facto standard for estimating kidney function...most of the time.

The gold standard test that doctors use for measuring kidney function is called 'creatinine clearance' (cree-AT-tuh-neeeen CLEAR-uhhh-nce) However, not many patients get this particular test because it is pretty darn inconvenient...and smelly. You have to collect all of your urine for 24 hours and keep it in the fridge. Not a lot of volunteers for this test...

Creatinine clearance is the volume of blood that the kidneys clear of creatinine in a given amount of time (and it is usually reported as milliliters per minute).

So, when kidney function decreases, creatinine clearance (the amount of blood that the kidneys are successfully 'cleaning') also decreases.

So remember: 'kidneys no work...creatinine clearance go DOWN'. (Note: this is easy to remember because it is the exact opposite of what you were initially thinking, and the opposite of what happens with serum creatinine. Most of medicine is like this.)

Now for the super tricky part just for those gunning for an A. There is a way to 'guestimate' creatinine clearance using serum creatinine...isn't that neat. And, that's probably the best way to determine renal function if a measured creatinine clearance is not available.

What you do is run the serum creatinine value through a fancy equation that will give you an estimated creatinine clearance, which is itself an estimate of kidney function. (Estimates of estimates of estimates...that's the kind of exacting science I live for.)

For adults, that equation is the famous 'Cockcroft-Gault equation corrected for ideal body weight and gender'...the equation everyone loves to hate. The Cockcroft-Gault equation (presumably named after Drs. Cockcroft and Gault...or maybe just Dr. Cockroft-Gault, or maybe Lara Croft), is generally considered very reliable since it has never been well validated in young patients, old patients, thin patients, fat patients...basically all the patients it gets used on. So go figure. Double bonus points if you can remember this:

For men, creatinine clearance =

((140- Age) ' IBW) / (72 ' SCr)

For women, creatinine clearance =

((140- Age) ' IBW ' 0.85) / (72 ' SCr)

Where Age is in years, IBW is ideal body weight in kilograms, and SCr is serum creatinine in mg/dl.

(For the algebraically-challenged and for anyone wanting help in calculating the results of these complicated equations, please visit this creatinine clearance calculator: http://www.medicationadvisor.com/creatinine/creatinine.asp)

Now once you run this a few times, you'll find that creatinine clearance for young healthy people is about 100 ml/min (we'll just leave off the 'ml/min' part from now on).

And, dead people have a creatinine clearance of about 0, depending on how healthy they are.

Everyone else falls somewhere in between.

(Now someone in the back of the room is saying, 'I just ran this on myself and I have a creatinine clearance of 150'. Well aren't you special? In fact, young good-looking people can have creatinine clearances of 130, 140, or more...but it doesn't do a whole lot of good since 100 is perfectly acceptable. In fact, it's just another case of overachiever overkill.)

Now, if someone has a creatinine clearance of 80, that means that they have about...80% kidney function.

And, if someone has a creatinine clearance of 50, that means that they have about...50% kidney function. (Are you following all of this?)

Many drugs that are eliminated by the kidney will require moderate dosage reductions once a patient's renal function is in the 40-60 range.

Patients in the 20-40 range will typically require very large reductions in dose.

And, patients who are in the 'less than 20' range will often need HUGE dosage reductions for medications eliminated by the kidney (or better yet, they'll need to take medications that are removed by some other organ altogether...if such an alternative is available).

One last tidbit to consider. Renal function declines as people age. No getting around that. But, the rate of decline is different for different people. By the time you're 50 years old, there is a reasonable chance you'll have moderate renal function (or worse)...by the time you're 80, you'll almost certainly have some important degree of renal impairment... and you probably won't even know it or feel it.

Now that you know more renal physiology than you ever, EVER wanted to know...let's get back to the main thread of this article...medication safety.

If you (or a loved one) are at risk for having decreased kidney function (and I'll tell you who such folks are in just a second), you need to step up to the plate and get a handle on this issue (because there is a very good chance that your physician and pharmacist either didn't have renal function data or didn't consider it when coming up with a dosage for you).

Here are the steps I recommend for everyone taking prescription or over-the-counter medications:

1) For everyone: If you have access to the results of a recent serum creatinine test (it is probably part of your annual physical and you may have gotten a copy), memorize it or write it down and then say to your physician or pharmacist when you get a medication, 'Say, I think my serum creatinine is about X. So, does this medication need any dosage adjustment in order to be safe for me?

2) If you are in one of the following categories, you should expect your physician and pharmacist to have considered your renal function before dosing a medication:

* known kidney disease;

* age greater than 50;

* history or heart attack, angina, stroke, or other artery blockages;

* history of diabetes (any type);

* history of high blood pressure;

* prior exposure to chemotherapy drugs;

* prior prolonged exposure to IV antibiotics;

* frequent use of pain medications (especially non-steroidal anti-inflammatory drugs, but others as well).

So you might say to your physician or pharmacist, 'Is this drug removed by the kidney, because I have condition X that could decrease kidney function and I just want to be safe.' If the drug is removed by the kidney, you might also ask the physician or pharmacist to tell you what your serum creatinine is...and if he or she does not have this information, a big red flag should be going up in your head.

3) If you are not in one of the categories in question 2 and you don't have a serum creatinine available, don't worry. You're probably safe. But you may want to ask your physician if there is a serum creatinine in your chart and if so, what it is.

4) If you are on dialysis of any sort, serum creatinine is not all that useful for dosing medications. Just make sure your physician and pharmacist are aware that you are on dialysis and perhaps ask, 'Now is this the usual dose for someone on dialysis?'

These are some of the steps I hope you will consider the next time you get a prescription or over-the-counter medication so you can be sure that that you (or your loved one) are getting the right dose.

© 2004 Timothy McNamara, MD, MPH

About The Author

Timothy McNamara, MD, MPH is a nationally prominent expert in medication safety and healthcare technology. For additional practical steps you can take to improve medication safety and a personalized report of your medication profile, go to: http://www.medicationadvisor.com/art2.asp


 
1.
Stress and Heart Disease
Stress and Heart Disease
About Stress:
The book "Streaa - from burnout to balance", authored by vinay joshi talks about the stress in detail. Simply put '
More >>
2.
Pill to help people live past 100
Pill to help people live 100 yearsComing Soon: A pill that will help you live past 100, says scientists. An international team is on track to develop what it cl
More >>
3.
Joint Pain Relief
Joint PainIf you joints are constantly killing you, here are three suggestions:

1. Traumeel is a product that has been used for years in Germany to rel
More >>
4.
How You Can Erase Low Back Pain Using the Latest Medical Techniques!
Low Back pain"If you're one the nine out of ten adults in the United States who suffers from low back pain, I have good news for you!" states Dr. Nathan Wei, a board-certi
More >>
5.
Eliminate Agonizing Hand Pain Quickly and Easily!
Hand PainAccording to Dr. Nathan Wei, "The hand and wrist are the mirrors of disease." While the cause of hand pain can be a localized problem, hand pain can also be the
More >>
6.
Amazing Shoulder Pain Reversing Secrets!
Shoulder painWhether you're a weekend athlete, or a gardener that overdid it, or a person with arthritis, there's hope for you. According to Dr. Nathan Wei, Clinical
More >>
7.
Medication Compliance Kit ... A Life Saver
Medical Compailance KitPill Proof LLC introduces the first, easy to use medication compliance kit for consumers and medical professionals. Owner, Jane Langdon
More >>
8.
Fifteen Ways to Fight Heel Pain
Heel PainThere are many different causes of heel pain, but the most common cause is plantar fasciitis (plan * tar fash* ee * I * tis). If you experience a sharp pain in y
More >>
9.
Understanding Tumescent Liposuction
LiposuctionTumescent liposuction is done using a local aesthetic. A large volume of saline solution containing the aesthetic and a drug called "Epinephrine" is injecte
More >>
10.
FDA Orders Search Engines to Stop Online Pharmacies
FDAHow Does Online Pharmacies Affect Pharmacy Leaders?

With cheaper drugs made available online, big pharmacy companies are losing control of their monopolistic
More >>
11.
Irritable Bowel Syndrome: Simple Self-Help Tips
Irritable Bowel syndromeIf you have been diagnosed with irritable bowel syndrome (IBS), you will know how difficult it is to treat. Doctors can be dismissive of IBS
More >>
12.
Another Cold Sore! Why Me?
Cold SoreAn estimated 85 million Americans have acquired the herpes simplex (cold sore) virus. And the majority had received the virus before the age of 3.


More >>
13.
A Fresh Start Plan for People With Neck Pain!
Neck Pain"If you have to deal with chronic neck pain, it can be a real struggle. I know? because I've had to do it myself," states Dr. Nathan Wei, a board-certified rheum
More >>
14.
Stem Cell Research
Stem Cell Research How To Buy Your Way Out Of An Early Death From An Incurable Disease.

How?... With private stem cell research, of course!?Stem cell resea
More >>
15.
Pain in the Butt. How to Deal with Hemorrhoids?
Joint PainThis is very sensitive area of your body. Too private. Nobody likes when something is wrong over there. However it happens.

Hemorrhoids occur
More >>
16.
Onychomycosis - One Of The Many Nail Fungus Out There
OnychomycosisMany natural changes in fingers and toenails come with age. Fine ridges, for example, may start developing from the cuticle of the nail tip. This and ot
More >>
17.
Do you suffer from Osteoarthritis? Here?s how to tell!?
Osteo ArthritisThe most common type of arthritis is osteoarthritis (OA). This type of arthritis is commonly referred to as wear and tear arthritis or degenerative a
More >>
18.
Five Secrets of High Blood Pressure Treatment
High Blood PressureThirty percent of human population has a high blood pressure and everyone has a 90% risk to acquire it during the rest of the life. As a resul
More >>
19.
CRP And Your Heart
CRP & Heart DiseaseMonitoring your CRP level is vitally important because it is one of the best indicators of heart disease. C-Reactive Protein has proven to be one of th
More >>
20.
Melatonin, Sleep Enhancement, and ADHD
Melatonin-sleep&ADHDMelatonin is a natural hormone, which is produced and secreted by the pineal gland. Melatonin plays an important role in the regulation of many hormo
More >>
21.
High Cholesterol Prescription Medications Can Kill You
High Blood CholesterolThe World Health Organization declares that heart disease is the number one killer worldwide. High cholesterol is a major contributor of hear
More >>
22.
A Look At Acid Reflux Treatment
Acid RefluxHeartburn is a by-product of digestion, specifically affecting the esophagus and the stomach. The esophagus is a tube that delivers food into the stomach, an
More >>
23.
Your Kidney Function Really Matters: A Lighter Look at What You Need to Know to Prevent Adverse Drugs
Kidney FunctionWhen you (or loved ones) are taking prescription or over the counter medications...there is a lot you should be worried about, and a lot that your ph
More >>
24.
Contact Lenses and Eye Glasses, How is Your Vision?
Contact LensNotice friends getting contact lenses and pulling out eye glasses?

"What do you recommend?"

I find myself asking people what
More >>
25.
Heart Disease: The Dangers Of Coronary Heart Attack And How To Avoid It
HEart DiseaseWhat is a coronary heart attack?
Are you at the risk of a coronary heart attack?
Here are some insights to help you...
A heart atta
More >>
26.
Causes and Types of Cerebral Palsy
Cerebral PalsyIn the case of Cerebral Palsy there is no one cause of this severe condition. There are many things that may increase the risk of this condition but wi
More >>
27.
Stevens-Johnson Syndrome
Stevens-Johnson SyndromeStevens Johnson Syndrome (SJS) is a severe and deadly allergic reaction to certain drugs, some proscription and some over the counter, whic
More >>
28.
Over The Counter Drugs: How To Safely Choose The Right Medication
Over The Counter DrugsWhat Medication Can Cure Me?

1. Am I expecting a cure? Some medications relieve symptoms ? that is, they stop the itching,
More >>
29.
Why R.I.C.E.?
R.I.C.EWhat is R.I.C.E. and why do you need it? One of the most recommended icing techniques for reducing inflammation and treating minor injuries is R.I.C.E., an acronym for
More >>
1. Dangerous Drugs
Dangerous DrugsVioxx, Celebrex, and Bextra: An editorial regarding dangerous drugs
More >>
2. New Treatment for Peripheral Neuropathy
Pherepheral NeuropathyMillions of Americans suffer with Peripheral Neuropathy and until recently there was
More >>
3. Moles, Warts & Skin Tags Remedy
MoleAre you worried about your moles, warts, and skin tags? Are scared about the idea
More >>
4. The Simplest Asthma Solution
AsthmaDuring the Democratic convention the Reverend Al Sharpton quoted a shocking
More >>
5. Natural Remedies For Treating a Cold
ColdSometimes it can be hard to escape that shivery feeling that happens when you get
More >>
6. Vibrational Medicine
Vibrational MedicineVibrational medicine attempts to treat people with various forms of pure energy.
More >>
7. How to Clean-up Your Allergies with 2 Easy Home Tips
AllergyIt's that time of year again when people who have allergies complain about nasal
More >>
8. Inflammatory Arthritis: Alternative Treatments
Inflammatory ArthritisThere are two main types of arthritis: inflammatory arthritis and osteoarthritis.
More >>
9. Powerful Essential Oils Kill Nail Fungus
Essential oil-Nail FungusFungal infection of the nails is the one of the most difficult of all disorders to cure.
More >>
10. Allergy Approaches through Lifestyle
AllergyWhat we do is just as powerful as what we eat to keep ourselves operating at our
More >>
11. Health Benefits of Tea
TeaStudies that support the health benefits of tea drinking keep filling the headlines.
More >>
12. Using Carrot Juice for Relieving Constipation
Carrot JuiceCarrot juices contain certain oils that work on the mucus membranes of the stomach
More >>
13. Eucalyptus: The Way to Smoother Breathing
EucalyptusThe eucalyptus is a popular Australian remedy that was first introduced to the
More >>
14. Getting Rid Of Gallstones Naturally
Gall StonesThe gallbladder is a small pear-shaped organ that sits on the right side of our
More >>
15. Water: The Best Medication Ever Created!
WaterHow much water do you drink every day? The majority of people do not drink
More >>
16. Mud Baths at Your Home Spa- the Pros and Cons
Mud BathMud baths are natural products you can use at your home spa.
More >>
17. Arthritis and Aromatherapy
AromatherapyArthritis is an inflammation of the joints and is characterized by pain, stiffness
More >>
18. The Effects of Diet on Infertiltiy
DietOverwhelmed by studies, research and the constantly changing diet, nutrition and
More >>
19. Enhanced Healing Through Music
MusicMusic has always been a very important part of our lives, from childhood to our
More >>
20. Home Remedies, Treatment To All Ailments By Herbal Homemade Remedies
Home RemediesGiven below the list of Best Home Remedies for all common diseases and
More >>
21. Constipation Relief With Fruits
FruitsHere's a group of fruits that you can use to get constipation relief. Use these
More >>
22. Fight Cancer With Broccoli Sprouts
BroccoliMom was right to insist on us eating our vegetables. She knew they built health
More >>
23. The Many Uses of Mint
MintThere are many varieties of mint plants. If you want to brew tea, you go Swiss mint,
More >>
24. Acupressure
AcupressureDeveloped in Asia over 5,000 years ago, acupressure is an ancient healing therapy
More >>
25. Herbal Medicine for Diabetes
DiabetesHerbs used in traditional Indian medicine to treat diabetes seems to lower blood
More >>
26. Reflexology
ReflexologyReflexology, an ancient art practiced by early Egyptians. Reflexology is a science
More >>
27. What is Homeopathy?
HomeopathyHomeopathy is a non-toxic system of medicine used to treat a wide variety of
More >>
28. Fitness-related Benefits of Massage
MassageAsk someone their reason for getting a massage and you're likely to hear
More >>
29. Why Detoxify?
DetoxifyHave you been hearing about detoxification more often? That's because
More >>
30. Pranic Therapy
Pranic TherapyPranic Therapy is an alternative system of Medicine using therapy with the Universal
More >>
31. Natural Medicine-Finding a Qualified Naturopath
NaturopathyNaturopathic medicine is currently the fastest growing segment of the alternative
More >>
32. Reiki
ReikiREIKI is a form of natural healing through direct application of Universal Life Force
More >>
33. Ayurveda, Indias Science of Life, Health and Longevity
AyurvedaAyurveda is India's ancient science life, health, and longevity. It is thought of by
More >>
34. Feng Shui for Your Health and Vitality
Feng ShuiHow many of us wake up in the morning feeling refreshed, happy and full of
More >>