Analgesics and Your Kidneys- Kidney Dialysis Information Centre

Analgesics and General Kidney Health

Analgesics is the technical term used by medics when talking about pain-killers. Everyone takes analgesics at some point in their life, and some people take them a bit more regularly than others. But what's the relevance to the state of your kidneys?

In general it is usually safe to take over the counter pain-killers such as aspirin, ibuprophen, paracetamol (acetaminophen) and other common analgesics, especially if you follow the directions on the packet. However if taken over a long period of time, or in excess of the recommended dose, you can end up harming your kidneys. Up to 5% of patients newly diagnosed with chronic kidney failure were regularly using analgesics. A scientific report sponsored by the National Kidney Foundation in 1995 summarised the results of reviewing 556 articles on analagesics and the kidneys. Later research in 2001 came to similar conclusions.

One recommendation from the NKF is that analgesics should be taken only under supervision by a doctor if the patient has kidney disease, heart disease, liver disease or high blood pressure. The same recommendation is given if you are elderly or on diuretics. Given that diabetics have a higher than normal chance of kidney damage, this advice can be extended to them as well.

Below is a summary of some key recommendations from the NKF on using analgesics safely.

Do not use them for more than 10 days for pain or more than 3 days for fever. If these problems persist for longer, see your doctor. (This applies to any one, not just those at risk of renal failure.)
Avoid prolonged use of products that contain mixtures of painkillers.
If you are taking analgesics, be sure to drink six to eight glasses of fluid a day.
If you have kidney disease, consult your doctor before using an analgesic. (I think this one is rather obvious, don't you?)
Tell your doctor about any/all the drugs you are taking, including over-the-counter products and dietary supplements.
Do read the warning label before taking any over-the-counter analgesic. (Again, rather obvious but often overlooked because the pain-killer or other drug "is well known so must be safe".)

The following are extracts from the 1995 report mentioned above.

Excessive use of paracetamol can damage multiple organs, especially the liver and kidney. In both organs, damage is not directly from the drug itself but from one of its metabolites. But it is acceptable to use this pain-killer if you only take it during episodes of discomfort from pain. Continually taking it every single day for weeks on end, however, is just not recommended. There is a weak association between habitually taking paracetamol and renal failure, hence this should be discouraged.

In patients with normal renal function, aspirin should not be taken within 48 hours of taking any nonnarcotic NSAID and vice versa (NSAID = Non Steriodal Anti Inflamatory Drug).

In patients with renal failure, aspirin should be avoided if possible, and if taken careful monitoring is required.

Taking a mixture of analgesics is not recommended.

But always remember - no web site is a substitute for proper medical advice from your own doctor. We are here to supplement, not to replace your medical advisor.