Lidocaine is a local anesthetic that’s been around since the 1940s. Research estimates that ~450,000 people used it in the United States alone in 2020. Lidocaine remains the drug of choice today for many medical procedures that require a mild anesthetic. Doctors prescribe it intravenously and topically to manage acute and chronic pain.¹
A topical anesthetic is a numbing agent in cream, ointment, liquid, spray, or gel form, although administering the drug via a patch is becoming a popular option. The active ingredients absorb into the skin, so the drug only affects the painful area, which is why it’s called a "local" anesthetic.
Let’s find out how lidocaine works and if it’s appropriate for reducing your shingles symptoms.
We make it easy for you to participate in a clinical trial for Shingles, and get access to the latest treatments not yet widely available - and be a part of finding a cure.
Like other local numbing agents, lidocaine works by blocking the pain signals the nerve cell membranes send to the brain.
If you've ever been to the dentist and had a shot of novocaine for a filling, that's a form of lidocaine injected into your jaw. You know how quickly that one side of your mouth goes numb, and it can be a few hours until the feeling comes back. While topical lidocaine isn't as strong as the drug your dentist uses, the concept is the same.
Simply put, shingles is the grown-up version of chickenpox.
Although there are hundreds of versions of the herpes virus in the world, only eight can affect humans. One of those is the varicella-zoster virus (VZV) that causes chickenpox (varicella) and shingles (herpes zoster).
The chickenpox vaccine has been widely available in the US since 2005. In the early 1990s, four million people—plus the millions who had contracted the virus earlier— got the varicella virus. Those millions are at risk for shingles as they get older.
That’s because the varicella-zoster virus remains dormant in your body when you get chickenpox. It can activate years later and show up as shingles, which can have nasty complications.
Shingles is similar to chickenpox in that there's an itchy rash with blisters that lasts two weeks or so, but that's where the similarity ends. The shingles rash is painful and itchy, and it’s usually confined to one of two areas on the body—the torso or face and neck. It can appear on either side but rarely both, whereas the chickenpox rash goes all over your body.
Shingles is contagious, but you can only spread it to people who have never had chickenpox or a vaccination against either.
The tricky thing about a herpes virus is that once the initial outbreak clears up, the virus goes dormant in your body until a perfect storm of events brings it roaring back to life.
VZV settles in the nerve roots at the base of your skull or along your spinal cord. Unless the virus reactivates, it stays undetected for the rest of your life.
So, what wakes the virus, creating that perfect storm that becomes shingles?
The primary culprit is a weakness in your immune system. Almost anything can trigger that weakening—a cold, extreme stress, or just getting older.
A weak immune system affects your central nervous system, so a dormant virus has the opportunity to attack the nerves where it's hiding. It multiplies (replicates) until it eventually reaches the nerves under the skin.
When the virus starts to replicate in skin cells, you get the inflammation and rash that are indicative of shingles. Nerve inflammation is what causes the pain you're feeling.
Shingles symptoms creep up on you and seem to happen all at once. Feeling tired and run down is common, but that could mean anything or nothing. A low fever, headache, or upset stomach are also early symptoms—but again, that could be anything.
These signs indicate a shingles outbreak is on the horizon:
Tingling, itching, or numbness of the skin
Burning, shooting pain
Fluid-filled blisters
Once the stinging starts, it's only a matter of hours until your skin turns red and bumpy, and the blisters erupt. Usually, the blisters dry up and scab over within ten days, although the scabs remain for a while.
When you have shingles symptoms, contact your doctor immediately. They can prescribe antiviral medications to speed the healing process and corticosteroids (prednisone) for the pain.
The complication of shingles that makes the disease so mentally and physically overwhelming is that the rash pain can linger for months or years after the rash heals. This condition is called postherpetic neuralgia (PHN), which can be debilitating.
This pain is why you should see your healthcare provider as soon as you recognize the symptoms of shingles; a corticosteroid can reduce the pain of the rash and reduce the chances of PHN.
Shingles has possible complications beyond PHN. If the blisters are on your face, they could spread to your eye. If the virus infects an eye, the damage can lead to blindness or other lasting damage.
Other complications include hearing loss, temporary facial paralysis, and in rare cases, encephalitis (brain inflammation).
Your doctor can prescribe one of three antiviral medications to treat the outbreak: Acyclovir, valacyclovir, or famciclovir. Additionally, they may recommend tricyclic antidepressants, steroids, or anticonvulsants for pain.
You can also treat shingles pain at home with topical solutions: Capsaicin creams and patches improve pain and itching. If you decide to try a capsaicin-based therapeutic, keep in mind that it is basically a cayenne pepper extract, so it may burn your skin.
Try to keep your mind off the pain, so you aren't tempted to scratch the itch. This may be the ideal time to binge-watch your favorite series, do crafts, or read a book. Calamine lotion and oatmeal baths may ease the itch of the drying blisters. Wear loose clothing in natural fibers, so nothing rubs against the rash.
Researchers around the world have conducted multiple studies to determine if topical lidocaine is an effective pain management tool against shingles rash pain and the lingering nerve pain that can persist after the rash has healed (PHN). Unfortunately, the only conclusion they’ve come to is maybe it helps.²
It's not for lack of trying that the results are inconclusive. The research teams used medicated patches, creams, gels in a 5% concentration, and sprays in an 8% concentration. They used cross-over (short-term random studies that won't alter the disease) and parallel-group (random subjects with no cross-over) trials.
Two studies used enriched enrollment with randomized withdrawal—if someone couldn't tolerate the lidocaine, they bounced out of the study.³
Seven of the studies monitored the respondents throughout multiple lidocaine applications, while five tested single-use applications.
All this research yielded little evidence that topical lidocaine has any real efficacy against shingles pain. One of the multiple-dose studies reported a pain intensity reduction of around 30–50%. Three of the single-dose trials had participants who were pain-free at some point or had a 20% reduction in pain levels. All but one of the studies found that lidocaine provided better pain relief than a placebo, but that’s not exactly a strong endorsement.
However, the authors determined that clinical evidence supports using topical lidocaine in individual cases, but they need more robust research to make definitive conclusions.
Lidocaine is available by prescription and over-the-counter (OTC). Salonpas, Aspercreme, Absorbine Jr, and IcyHot contain lidocaine and come in various forms. The highest OTC lidocaine concentration is 5%, but some research indicates that a higher percentage does not equate to greater pain relief.
An article in the Aesthetic Surgery Journal referenced a study that found several factors determine how much anyone will get from a topical lidocaine application. Your liver function impacts how your body processes lidocaine, and the drug form (i.e., patch, gel, etc.) also makes a difference.⁴
This same study also proves that OTC lidocaine is better for pain than a prescription dose—it has a higher level of absorption and remains in the bloodstream eight hours after application.
Topical lidocaine comes in three forms: Cream (or gel), patch, and spray. Always prepare your skin before applying, whichever lidocaine delivery method you choose:
Clean the area you're treating with rubbing alcohol or witch hazel.
Wash your hands with soap and warm water, rinse thoroughly, and dry.
Apply the recommended amount and gently rub it into the skin.
Wash your hands thoroughly again.
Don't use the lidocaine until your blisters are healing—any contact with an open blister can cause another infection.
These creams usually come in a tube in a range of lidocaine concentrations. Aspercreme, IcyHot, and Nervive are all commonly available over the counter in a range of strengths and applications. You can also save a little money with a generic drugstore brand.
You can also get lidocaine in a spray. A study testing a viscous lidocaine solution and a spray application found that the spray was just as effective in controlling discomfort and pain for GI surgery patients, and it was preferable overall.⁵
You can get pretty much the same brands and strengths of lidocaine in spray bottles.
Transdermal patches are available OTC in a 4% concentration, but your doctor may prescribe a 5% patch. The instructions for wearing a patch are different, so consult your doctor before putting one on.
Absorbine Jr, Aspercreme, and Salonpas come in a patch version. They continuously transmit lidocaine to the skin for as long as you wear the patch. Most patches recommend use for no more than eight hours, and you can wear up to three at a time.
The protocol for applying a patch is similar to a cream or spray: Apply it to clean skin with clean hands. Consider these additional steps and precautions for wearing a patch:
Choose an area where your clothes won't rub against the patch.
If you feel any burning or stinging, remove the patch immediately.
You can customize the size of your patch with scissors.
Only unpeel the backing when you're ready to apply the patch.
Remove old patches before applying new ones.
If the shingles rash is on your face, take extra care in applying any lidocaine. If you accidentally ingest any, or it comes into contact with your eyes, you could experience significant side effects. Numbness in the mouth and throat could lead to problems swallowing and even breathing, while any medication in your eyes can cause your eye to go numb.
Lidocaine may ease the pain if you still have PHN after the rash has healed, and you've tried steroids. Don't apply any topical cream, spray, or gel to an active rash without your doctor's approval.
The best way to prevent shingles is to get the Shingrix vaccine. The National Institute on Aging recommends that adults over 50 should get both doses. They're available at some pharmacies or your doctor's office. The vaccine is free if you are over 65, and Medicare Part D and private health insurance may cover some or all of the cost. If you had the earlier shingles vaccine, Zostavax, you should update that with the newer version, Shingrix.
There are times when you should not get the shingles vaccine:
If you had an allergic reaction to an earlier dose
If you currently have shingles
If you’re running a fever or are sick
Ask your doctor if you’re unsure whether you should get the vaccine.
If you have shingles or PHN, topical lidocaine may reduce the pain associated with the affected area. Before you start any at-home treatment for shingles, check with your doctor.
If you have any side effects from the lidocaine, stop using it and let your doctor know you had a bad reaction. Finally, speak to your doctor about getting the vaccine if you're over 50.
Sources
Lidocaine | Clincalc.com
Other sources:
Lidocaine (2022)
Topical anesthesia (2015)
Chapter 68 herpesviruses (1996)
Chapter 22: Varicella; Epidemiology and prevention of vaccine-preventable diseases 14TH edition | Centers for Disease Control and Prevention
Shingles | National Institute on Aging
Complications of shingles | Centers for Disease Control and Prevention
Parallel group- or cluster-randomized trials (GRTs) | NIH: National Institute on Aging
Lidocaine transdermal patch | MedlinePlus
We make it easy for you to participate in a clinical trial for Shingles, and get access to the latest treatments not yet widely available - and be a part of finding a cure.