NSAID (Non-Steroid Anti-inflammatory Drug) - A friend or foe for acute pain ?

From 1 to 10 , please scale your level of pain.

Pain is a very subjective sensation.

There are many drugs being developed and marketed for pain. Apart from paracetamol (also known as acetaminophen), NSAIDs are the drugs that most commonly used to treat pain and/or inflammation. For example, NSAIDs could be used for osteoarthritis (eg. knee pain),  sprains, strains, period pain (dysmenorrhoea), gout pain, headache, migraine.

Some of the examples for NSAIDs include ibuprofen,  diclofenac, naproxen, mefenamic acid, celecoxib, meloxicam. The list goes on.

What NSAIDs do ? 

NSAIDs works by inhibiting COX  (either selective or non-selective) , thereby stopping the production of prostaglandins (pro-inflammatory factors). This can then reduce the inflammation and pain, giving us the pain relief we need.

NSAIDs are "nasty" drugs with adverse side effects? 

 We all know that nothing comes with no cost. In medical field, we used drugs (medicines) to treat ailments and diseases. Yet, medicine, itself, can bring side effects. This applies to all medicines, from causing common side effects - nausea, vomiting, diarrhoea to some even more serious ones such as agranulocytosis, heart attack, renal failure.

So do NSAIDs.

Therefore, I would say correct and proper use of medicines are much more important in preventing side effects. Even so, side effects may still occur.

Let's look at some of the common side effects of NSAIDs and how we deal with them when it does happen. 

1.  GI side effects

Most of drugs can cause stomach upset. NSAIDs can cause stomach upset, diarrhoea,  gastrointestinal bleeding or ulceration.

Selective COX-2 inhibitors are believed to reduce risk of GI side effects, however,  studies have not shown significant differences of GI side effects between non-selective and selective COX inhibitors.

If the patient has acute pain and need a short course of NSAIDs, can consider giving gastro protective agents such as proton pump inhibitor (e.g. omeprazole) or H2 antagonist (e.g. ranitidine) at the same time to reduce the risk of bleeding or ulceration.

Alternatively, can give paracetamol plus codeine (such as Panadeine) to alleviate the pain.

Diclofenac and ibuprofen appears to be the NSAIDs that cause less GI effects (5). 


2. Cardiovascular side effects
- blood pressure increases (because of NSAIDs can cause sodium and water retention), may exacerbate pre-existing hypertension 
-increase risk of cardiovascular events such as heart attack (myocardial infarction) and stroke.

If the patient has had recent cardiovascular events (heart attack or stroke), AOVID taking NSAIDs. Use alternative pain killer such as paracetamol, or add in codeine phosphate if needed.

3. Renal side effects

- If you have renal problems,
OR
-If you are taking blood pressure pills (such as diuretics or ACEI (angiotensin converting enzyme inhibitor) or ARB(angiotensin II receptor blocker),

You need to be extra careful , as NSAIDs may predispose or increase the risk of acute renal failure.  Please do let your doctor or pharmacist know.

4. Hypersensitivity reactions

Some of the patients may develop allergic reactions such as angioedema (swelling), difficulty in breathing (because of swollen airways) or skin reactions such as rashes upon taking NSAIDs.

Stop taking NSAIDs immediately if hypersensitive reaction develops. And, tell a doctor or a pharmacist when you are needing something for pain treatment next time. Tell them you are allergy to NSAIDs and describe what happened.


All NSAIDs have the risks of inducing all these side effects - to certain extent depending on the particular NSAID . For example, diclofenac poses highest risk of cardiovascular events.


Have you ever heard of stories about patients suffer from acute renal failure after having few doses of ibuprofen (NSAIDs). I heard about one and I was not too sure the exact cause behind the story, however, I want to make a point that the side effects of NSAIDs could get serious!

****Triple whammy ***

One of the factors we need to consider when it comes to taking NSAIDs is the interactions with other medications the patient is taking.


Combination use of NSAIDs (or selective COX-2 inhibitor)  AND diuretics  AND  ACEI/ARB
should be avoided.

Using these three classes of medicines at the same time increase the risk of acute renal failure. That's the last thing we wanted for the patient.

Do remember this when a customer come in and ask for pain killer (NSAIDs), especially the elderly or when the customer is dehydrated.

In short,

If the patient is taking diuretics and ACEIs (or ARBS) for their blood pressure control, avoid use of NSAIDs, if possible, or use lowest effective dose for shortest period.

DO NOT take NSAIDs when you are dehydrated.


Patient advice 


Take NSAIDs following the dosing regime. Take them with a large glass of water and food.

(Do inform the patient the importance of drinking enough water while taking NSAIDs to reduce risk of kidney side effects.)

Example of normal dosing regime for adult dose :

Ibuprofen - ONE or TWO tablets (200mg to 400 mg) up to THREE or FOUR times daily. Maximum of 2.4g in 24 hours.

Diclofenac - 75-150 mg daily in TWO or THREE divided doses. Maximum of 200mg in 24 hours.

Naproxen sodium - 250-500 mg TWO or THREE times daily.Maximum of 1250 mg in 24 hours.

Meloxicam - 7.5 - 15 mg ONCE daily. Maximum use of 15mg in 24 hours.

NOTE: the dosing regime above is only a reference. Always talk to a doctor or a pharmacist regarding your condition.

In short, 

NSAIDs are ubiquitous medicines on the market. You can get NSAIDs easily. However, use NSAIDs wisely. For acute pain, NSAIDs are useful in reducing the pain and inflammation and keep you going in your daily activities.


However, always be aware of the possibilities of the side effects.

For long term management, always bear in mind the possibilities of GI side effects e.g. bleeding and risk of cardiovascular events. (A NSAID with a longer half life such as naproxen can be considered for easily daily ONCE or TWICE daily dosing,which can increase patient compliance and adherence. 

Watch out for the side effects and do remember that NSAIDs (e.g. ibuprofen or diclofenac) can interact with some of the medicines you are taking. If you are on long term medications, talk to a pharmacist or a doctor to seek for advice.

AVOID NSAIDs while someone is pregnant, especially during the third trimester.  ( Paracetamol is always the safer option).

References 

1. http://www.bpac.org.nz/BPJ/2013/October/nsaids.aspx

2. Australian Medicines Handbook 2016

3. New Zealand Formulary

4. http://www.saferx.co.nz/full/triplewhammy.pdf

5. AMH handbook