Many people assume that if you rub a medication onto your skin it doesn’t go very far. That’s why there is little concern about side effects from gels or creams such as topical diclofenac. But the skin is not an impenetrable barrier.

Researchers have known for years that many medications can be absorbed through the skin and into the systemic circulation. They include nitroglycerin for the heart, fentanyl for pain, testosterone and estradiol for hormone replacement therapy, corticosteroids for inflammation and scopolamine for motion sickness.

Is Topical Diclofenac Safe for Everyone?

Over the years we have written that topical NSAIDs may be safer than oral versions of ibuprofen or diclofenac. That was based in part upon an overview by the Cochrane Collaboration (Cochrane Database of Systematic Reviews, June 11, 2015): 

“Topical NSAIDs provided good levels of pain relief in acute conditions such as sprains, strains and overuse injuries, probably similar to that provided by oral NSAIDs. Gel formulations of diclofenac (as Emugel), ibuprofen, and ketoprofen, and some diclofenac patches, provided the best effects. Adverse events were usually minimal.”

That said, some people are extremely sensitive to NSAID toxicity. Even topical diclofenac can cause harm to these individuals. Here are some examples:

Q. You’ve written about Voltaren gel for arthritis pain. I cannot use this drug, as it causes me severe stomach pain and acid reflux. I wish I could use it for my sore joints.

My aunt died from using an NSAID. It gave her an ulcer that led to infection and death.

I can’t believe we can buy NSAIDs without a prescription in this country. They can kill you and are known to cause ulcers even when people are unaware of the damage until it is too late.

A. You are correct that nonsteroidal anti-inflammatory drugs (NSAIDs) such as diclofenac, ibuprofen (Advil, Motrin IB), meloxicam and naproxen (Aleve) can cause stomach ulcers (Expert Review of Gastroenterology & Hepatology, June 2016).  Such complications can indeed be deadly.

Many people can apply topical NSAIDs without the complications associated with oral drugs like celecoxib, meloxicam or naproxen. Even so, there are some individuals who are super sensitive to NSAIDs in general and topical diclofenac in particular.

Stories from Other Readers:

Anonymous shared this story about Voltaren Gel:

“My doctor gave me Voltaren gel samples to try for joint pain. When I looked at the warnings (I cannot tolerate even tiny amounts of NSAIDs, due to other bad drug reactions that ruined my stomach) I asked about them. He waved them off, saying ‘They HAVE to say that because it’s an NSAID.’

“He said the gel was better because it wouldn’t affect my stomach. I did fine on the samples, and paid $167 for a prescription for several big tubes of Voltaren. As always, I was using a very low dose, less than half the recommended dose and only once or twice a day.

“After a couple weeks, I woke up with severe stomach pain. My stomach began to feel pretty awful in general. I asked my pharmacist and he said the gel gets into the bloodstream, and goes everywhere in the body. It causes all the side effects of any oral NSAID, i.e., everything listed on the box as a warning was true.

“Yes, it was causing my stomach pain and who knows what else.) That’s $167 down the drain. I can’t use the stuff. I tried a couple times later to just use a tiny dab or two of it, and it upset my stomach again”

Brenn reports a similar problem:

“I tried the Voltaren gel because oral NSAIDs cause extreme stomach distress, acid reflux, and most frightening, atrial fibrillation. My cardiologist said it was an inflammation in the lining of my heart. Using the gel caused the same problems in both me and my neighbor. If I only use a small amount, occasionally, the symptoms are mild, but it really doesn’t do much for relief.”

Diane has congestive heart failure. Topical diclofenac is not a good idea for her!

“I have a question: What about topical NSAIDs? I’ve been prescribed Voltaren gel for neuropathy in both feet. If I use it every day, I begin to get burning in my stomach. The prescription insert literature suggests that yes, it is absorbed. I also have edema in the extremities because I have congestive heart failure. I may be noticing an increase in this on the Voltaren gel. Does anyone know the answer to the gel vs. oral question?”

For most people, occasional use of oral ibuprofen or naproxen is not highly dangerous. Many people take these medicines daily, however, to ease the pain of arthritis. They are at risk for a range of serious side effects. The FDA has black box warnings on topical NSAIDs. Here is a link to learn more about this confusing subject:

How Safe Are Topical NSAIDs Like Voltaren Gel?

We discuss safer options to manage arthritis pain in our eGuide to Alternatives for Arthritis

Related People's Pharmacy Health Guide

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