Topical Analgesics: Lidocaine, Capsaicin, and NSAID Gels Explained

• By Liz MacRae
• 16 Nov, 2025
• 1 Comments

What Are Topical Analgesics and Why Do They Work?

Topical analgesics are pain relievers you apply directly to your skin-no swallowing pills, no injections. They’re designed to block pain signals right where it hurts, without flooding your whole body with medicine. This makes them ideal for sore muscles, arthritic joints, or nerve pain like post-shingles pain. Unlike oral painkillers, they rarely cause stomach upset, liver strain, or kidney issues because very little of the drug enters your bloodstream.

Three main types dominate the market: lidocaine patches, capsaicin creams and patches, and NSAID gels like diclofenac. Each works differently. Lidocaine numbs nerves like a local anesthetic. Capsaicin burns your pain nerves into submission. NSAID gels reduce inflammation at the surface. All three avoid the risks of opioids and oral NSAIDs, which is why doctors now recommend them as a first step for localized pain.

Lidocaine Patches: The Numbing Solution

Lidocaine patches, like Lidoderm®, deliver 5% lidocaine through the skin to block pain signals from damaged nerves. They’re FDA-approved for postherpetic neuralgia-pain that lingers after shingles-but many people use them for other nerve-related pain, like diabetic neuropathy or pinched nerves.

Here’s how it works: lidocaine stops sodium channels in nerve cells from firing. No signal, no pain. The patch is worn for 12 hours, then removed for 12 hours. You can use up to three patches a day, but never more. Systemic absorption is tiny-only about 63 mg over 12 hours. That’s less than 10% of the amount that could cause heart rhythm problems.

Side effects are mild: redness or itching at the patch site happens in 5-15% of users. But if you’ve got open wounds, burns, or sensitive skin, skip it. The patch doesn’t penetrate deep-only about 5-10 mm-so it won’t help with hip or spine pain. It’s best for surface-level nerve pain, like a burning sensation along the ribs or foot.

Capsaicin Patches: Burn to Heal

Capsaicin comes from chili peppers. Sounds strange, right? But it’s one of the most effective treatments for chronic nerve pain. The high-strength 8% capsaicin patch, called Qutenza®, is applied by a healthcare provider in a clinic. Why? Because it hurts-badly-at first.

When capsaicin touches your skin, it activates TRPV1 receptors, which normally respond to heat. Your nerves fire intensely, creating a burning sensation that can last 30-60 minutes. Then, something surprising happens: the nerves become exhausted. They stop sending pain signals. This effect can last up to three months after one 30-minute application.

Studies show it reduces postherpetic neuralgia pain by about 30-50% in people who stick with it. But 30-50% of patients quit because the initial burn is too intense. That’s why it’s not sold over the counter. Low-dose capsaicin creams (0.025-0.1%) are available without a prescription, but they’re much weaker and need to be applied four times daily for weeks before you feel relief.

Never apply capsaicin near your eyes, mouth, or genitals. Wash your hands right after. And don’t use it if you have broken skin. The 2023 FDA REMS program requires special training for providers because misuse can cause serious irritation.

NSAID Gels: Anti-Inflammatory on the Spot

NSAID gels-like Voltaren (diclofenac 1%) and Flector (flurbiprofen)-work by blocking COX enzymes right where you apply them. These enzymes make prostaglandins, the chemicals that cause swelling and pain. By stopping them locally, the gel reduces inflammation without affecting your stomach or kidneys like oral NSAIDs do.

Microdialysis studies show tissue concentrations of diclofenac in the joint area can be 10 to 100 times higher than in your blood. That’s why it’s so effective for knee osteoarthritis. One study found 60% of users reported at least 50% pain reduction after four weeks. For deep joints like the hip? Only 20% improvement. That’s because the gel can’t reach far enough down.

Apply it four times a day-about a 2-4 inch ribbon each time. Rub it in gently. Don’t cover it with a bandage unless your doctor says so. Wait at least 30 minutes before showering or swimming. Peak effect kicks in around 1.5 hours after application.

Side effects? Skin redness, dryness, or itching in 10-20% of users. Rarely, allergic reactions happen. The FDA requires a warning on all NSAID products about possible heart risks, but topical versions carry far less risk than pills. Still, avoid them if you have a history of heart failure, high blood pressure, or kidney disease.

How Do They Compare? Real Numbers, Real Results

Not all topical pain relievers are created equal. Here’s how they stack up based on clinical data:

NNT means how many people need to use it for one person to get meaningful relief. Lower numbers are better. So NSAID gels win for acute pain like sprains-only 2.7 people need to use it for one to feel better. Capsaicin is better than lidocaine for nerve pain, but the initial burn turns people off. Lidocaine is gentle but less powerful.

Who Should Use Them? Who Should Avoid Them?

Topical analgesics are perfect for:

• Older adults with osteoarthritis who can’t take oral NSAIDs
• People on multiple medications (polypharmacy) who want to avoid drug interactions
• Those with stomach ulcers, kidney disease, or liver problems
• Patients wanting to reduce opioid use

But avoid them if you:

• Have open wounds, rashes, or broken skin at the application site
• Are allergic to aspirin or NSAIDs (for NSAID gels)
• Have severe heart failure or uncontrolled high blood pressure
• Are pregnant, especially in the third trimester (NSAIDs can affect fetal circulation)

For capsaicin, always get the 8% patch applied by a professional. Never try to self-administer it. For lidocaine, don’t use more than three patches a day. For NSAID gels, stick to the recommended dose-more doesn’t mean faster relief.

Real People, Real Results

Patients who stick with topical analgesics often say the same things:

• "I stopped taking ibuprofen every day and my stomach feels fine." - u/KneeOA_Sufferer, Reddit
• "The capsaicin patch hurt like hell for an hour, but my pain dropped from 8/10 to 3/10 and stayed there for weeks." - u/ChronicPainWarrior
• "I thought Voltaren was just a placebo. But after four days, I could walk to the mailbox without limping." - 68-year-old patient, UK primary care survey

But there’s frustration too. Many users say:

• "It works sometimes, but not always. I think my dry skin stops it from absorbing."
• "The gel is messy. I get it on my clothes."
• "I didn’t rub it in enough. I thought just spreading it on was enough."

Studies show 60% of first-time users apply too little gel. The key is using the full recommended amount and massaging it in gently for 30 seconds. Don’t just dab it on.

What’s Next? The Future of Topical Pain Relief

Scientists are working on better ways to get medicine deeper into the skin. One new nanoemulsion diclofenac gel showed 2.3 times more drug in the tissue than the old version-without raising blood levels. That could mean better relief for hip or shoulder pain.

Researchers are also testing resiniferatoxin (RTX), a super-potent cousin of capsaicin, for osteoarthritis. It’s 1,000 times stronger, but it doesn’t absorb well yet. If they solve that, it could replace injections.

And menthol? It’s not just for cooling. New studies show it activates TRPM8 receptors, which may help block pain signals. Some future creams might combine menthol with low-dose lidocaine or capsaicin for dual action.

How to Use Them Right

Here’s the simple checklist most patients miss:

1. Check your skin. No cuts, rashes, or sunburns where you’re applying.
2. Use the right amount. For gels: a 2-4 inch ribbon. For patches: one per area, max three a day.
3. Massage gently. Don’t just spread it-rub it in for 30 seconds to help absorption.
4. Wait. Don’t shower or cover with a wrap for at least 30 minutes.
5. Wash your hands. Especially after capsaicin or NSAID gel.
6. Be patient. Capsaicin takes days. NSAID gels take hours. Lidocaine works fast but doesn’t last long.

Most people give up too soon. It takes 2-3 tries to get the technique right. If it doesn’t work after two weeks, talk to your doctor. Maybe you need a different type-or a combination.

Bottom Line: Topical Pain Relief Is Real-If You Use It Right

You don’t need opioids. You don’t need to risk your stomach or kidneys. Topical analgesics are proven, safe, and effective for localized pain. Lidocaine for nerve pain. Capsaicin for stubborn nerve damage. NSAID gels for inflamed joints and muscles.

They’re not magic. But they’re the smartest first step for millions of people with chronic pain. Use them correctly, and you might never need a pill again.

Topical analgesics aren’t the answer for every pain. But for the millions dealing with joint aches, nerve pain, or muscle strains, they’re a quiet revolution in pain management. No pills. No risks. Just relief where you need it.