Health Tips

Painkillers and kidneys

According to a study regarding the trends and patterns of analgesic prescribing in Malaysia public hospitals from 2010 to 2016, tramadol utilization was the highest compared to other painkillers like individual nonsteroidal anti-inflammatory drugs (NSAIDs), including ketoprofen, diclofenac, and celecoxib.

Tramadol 50 mg (Tramal®) tablets

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Diclofenac (Voltaren®) 50 mg tablets

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Celecoxib 200 mg (Celebrex®) tablets

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How do painkillers affect your kidneys?

Tramadol

Tramadol itself does not directly harm the kidneys. 90% of tramadol and its metabolites are excreted in the urine, hence for patients with advanced chronic kidney disease (CKD), tramadol and its metabolites accumulate in the body causing side effects like drowsiness.

Advanced CKD is where the damage in kidneys are very severe that the kidneys cannot filter blood as usual leading to accumulation of waste in the body. 

NSAIDs

NSAIDs are famous for their direct kidney damage. 

• NSAIDs constrict kidney blood vessels leading to reduced waste filtration

• NSAIDs has modest worsening of underlying high blood pressure

• NSAIDs can cause swelling, and electrolyte imbalance 

• NSAIDs increase the risk of kidney cell cancer

Therefore, the risk of acute kidney failure is increased in those with existing kidney diseases.

Paracetamol

Panadol, well known for its anti-fever effect, possess pain-killing effects as well. Typically the safest recommended painkiller is used in patients with kidney disease should still be used under supervision by a doctor. 

However, it is important to take note that the drug can be harmful if used at high doses or very frequently. Therefore, Panadol is associated with kidney damage when it is taken more than the maximum dosage allowed for a long period. The maximum adult dose is 1 gram per dose and 4 grams per day. 

So, how should you choose your painkiller?

First of all you need to identify whether it is an acute pain or a chronic pain.

Acute pain: a sudden pain caused by an injury.

Chronic pain: a persistent pain (including nerve pain) that is ongoing and has been developed for a long time from prolonged injury.

Next, how painful are you?

Most commonly used pain assessment tools are McGill Pain Questionnaire (verbal), Wong-Baker faces (visual) and a simple 0-10 numerical pain scale (numerical), as shown below.

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Choose your painkillers (based on WHO analgesic ladder)

Generally, topical painkillers have fewer side effects than oral painkillers and are preferred over oral ones. however, prolonged use of any painkiller cream or ointment increases skin absorption and blood circulation accumulation. 

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All in all

There is no one-painkiller-fit-all solution for every of us. Before you choose your painkiller, make sure you get proper advice from healthcare professionals such as doctor or pharmacist. 

Visit a doctor if you have signs of kidney disease already.

Medically reviewed by Ashwini Nair, MB BCh BAO.

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References:

1. Zin CS, Nazar NI, Rahman NS, et al. Trends and patterns of analgesic prescribing in Malaysian public hospitals from 2010 to 2016: tramadol predominately used. J Pain Res. 2018;11:1959-1966. doi:10.2147/JPR.S164774

2. Management of chronic pain in advanced chronic kidney disease - UpToDate. Accessed March 3, 2022. https://www.uptodate.com/contents/management-of-chronic-pain-in-advanced-chronic-kidney-disease?search=tramadol%20and%20kidney&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H1838178070

3. Nonselective NSAIDs: Overview of adverse effects - UpToDate. Accessed March 3, 2022. https://www.uptodate.com/contents/nonselective-nsaids-overview-of-adverse-effects?search=nsaids&source=search_result&selectedTitle=3~147&usage_type=default&display_rank=2#H18852068

Written by

DOC2US Editorial Team