You should wonder if a medication you often take for pain is safe. There are some misconceptions about NSAIDS (ibuprofen, naproxen, Motrin, Advil) and some truths. How much can or should you take and is it bad for your liver or kidneys? Every week I’m asked this question.
For the treatment of mild to moderate pain, minor fever, and acute or chronic inflammatory conditions 200 mg to 400 mg of ibuprofen will work, and is comparable to 650 mg of acetaminophen (Tylenol) or aspirin. Generally taken every 6 to 8 hours, the maximum dose of NSAIDs per day is 2400 mg which is 12 over-the-counter tablets.
Ibuprofen and other NSAIDS rarely affect the liver. Unlike acetaminophen (Tylenol) most NSAIDs are absorbed completely and have negligible first-pass hepatic (liver) metabolism. In other words, the way NSAIDS are metabolized makes liver toxicity (hepatotoxicity) very rare. Estimates are that 1 in 100,000 NSAID prescriptions result in acute liver injury. Generally NSAIDs are very liver-safe.
It’s about the kidneys:
NSAIDs have important adverse effects on the kidney that you should know about.
Here is the science behind the problem. Ibuprofen and other NSAIDs inhibit prostaglandins, and that can cause a problem because prostaglandins dilate blood vessels leading to the kidneys. Inhibiting prostaglandins may lead to kidney ischemia (dead tissue from decreased blood flow) and thus acute kidney injury.
A simple blood test may show a rise in creatinine if your kidneys are being affected, usually seen within the first three to seven days of NSAID therapy. Acute kidney injury can occur with any NSAID though naproxen seems to be a bigger culprit. In one study, folks who took NSAIDs had twice the risk of acute kidney injury within 30 days of starting to take the NSAIDs. Good news is it’s reversible if you stop taking them.
In people with high blood pressure, taking NSAIDs long term may worsen underlying high blood pressure. People with kidney problems at baseline more often get in trouble with NSAIDs, but if you are taking ibuprofen for long periods of time it’s not a bad idea to have a check of your kidney function with a quick blood test. Remember, acute kidney injury from NSAIDs doesn’t cause any symptoms.
Sum it up:
NSAIDs are safe for the liver, but can cause a problem with kidney function that is reversible if you stop taking them. Generally safe but worth paying attention to.