Choosing the Right OTC Pain Reliever
Not all pain relievers work the same way. Learn the differences between acetaminophen, ibuprofen, and naproxen — and get guidance from your Nepean pharmacist on using them safely.
Acetaminophen, Ibuprofen, and Naproxen — What's the Difference?
The three most common over-the-counter pain relievers in Canada work through different mechanisms. Choosing the right one depends on what you are treating, your other health conditions, and any other medications you take. Here is a quick comparison:
Acetaminophen (Tylenol, generic)
Ibuprofen (Advil, Motrin, generic)
Naproxen Sodium (Aleve, generic)
Who Should Use NSAIDs With Caution or Avoid Them?
NSAIDs (ibuprofen, naproxen) are not appropriate for everyone. Speak with your pharmacist or doctor before using them if any of the following apply to you:
- Kidney disease — NSAIDs reduce blood flow to the kidneys and can worsen kidney function.
- History of stomach ulcers or gastrointestinal bleeding — NSAIDs irritate the stomach lining.
- Heart disease or recent heart attack or stroke — NSAIDs can increase cardiovascular risk.
- Taking blood thinners (warfarin, apixaban, rivaroxaban) — risk of serious bleeding increases.
- Taking ASA (Aspirin) daily for heart health — combining with another NSAID increases GI bleed risk.
- Third trimester of pregnancy — NSAIDs can affect fetal kidney development and the ductus arteriosus.
- Older adults (65+) — higher risk of all NSAID-related side effects.
Acetaminophen and Liver Safety
Acetaminophen is one of the leading causes of acute liver failure when taken in excess — often accidentally. The risk is higher if you drink alcohol regularly, have pre-existing liver disease, or take other products that contain acetaminophen without realizing it.
Always check the labels of all medications you take. Many cold, flu, and sinus products, as well as some prescription pain medications, contain acetaminophen. Taking multiple products that contain it at the same time is easy to do without realizing it.
- Read ingredient labels on all OTC products — look for 'acetaminophen' or 'APAP'.
- Do not exceed 4,000 mg per day (most adults) — many experts recommend staying under 3,000 mg.
- Limit alcohol to no more than 1–2 drinks per day if using acetaminophen regularly.
- Use the lowest effective dose for the shortest time needed.
When to See a Doctor
OTC pain relievers are meant for short-term use. See a doctor or visit a clinic if:
- Pain is severe, sudden, or unexplained.
- Pain lasts longer than 10 days in adults or 5 days in children.
- You have a fever above 39°C that does not respond to medication.
- You experience stomach pain, dark stools, or blood in your urine while taking NSAIDs.
- You need pain medication daily for more than a few days.
Frequently Asked Questions
Can I take acetaminophen and ibuprofen at the same time?
Yes, in many cases they can be taken together because they work through different mechanisms. Some healthcare providers recommend alternating the two for more consistent pain control — for example, acetaminophen at 8am, ibuprofen at 12pm, acetaminophen at 4pm, etc. However, always stay within the recommended maximum dose for each drug and speak with your pharmacist before combining them.
How much acetaminophen is safe to take per day?
For healthy adults, the maximum recommended dose is 4,000 mg (4 g) per day, but many pharmacists recommend staying under 3,000 mg per day to allow a safety margin. Remember that acetaminophen is found in many combination products — such as cold and flu medications and prescription opioid combinations — so it is easy to accidentally exceed the limit. People who drink alcohol regularly or have liver disease should use a lower dose or avoid it altogether.
Are ibuprofen and naproxen safe for older adults?
NSAIDs like ibuprofen and naproxen are generally used with more caution in older adults because they carry a higher risk of stomach bleeding, kidney problems, and cardiovascular events in this age group. Acetaminophen is often preferred as the first-line pain reliever for older adults, when appropriate. Your pharmacist can help you choose the safest option for your situation.
When should I see a doctor instead of using OTC pain relievers?
You should speak with a doctor or go to a clinic if: your pain is severe or getting worse; it lasts more than 10 days (adults) or 5 days (children); you have a fever above 39°C that doesn't respond to medication; you experience pain after an injury that may involve a fracture; or you are unsure what is causing the pain. Your pharmacist can also help you decide whether a doctor visit is warranted.