Lidocaine Patch for Back Pain: What to Know
Medically reviewed by Femi Aremu, PharmD
Lidocaine patches are in a drug class called local anesthetics that relieve pain in a small area of your body. Lidocaine patches are available either by prescription or over-the-counter (OTC or nonprescription).
The Food and Drug Administration (FDA) approved lidocaine 5% or 1.8% patches for relieving postherpetic neuralgia (PHN) pain. PHN is long-term nerve pain, which is a common complication of shingles. These lidocaine patches are prescription-only.
OTC lidocaine 4% patches can be used to relieve minor aches and pains, including back pain.
However, there isn't enough evidence to recommend the use of lidocaine patches as an effective method of pain relief.
This article discusses what you should know about lidocaine patches for back pain, including how well they work, side effects, how to use them, and more.
Getty Images / sakai000
What Is a Lidocaine Patch?
The lidocaine patch is in the local anesthetic drug class. It is available in prescription and OTC forms.
OTC forms of lidocaine patches come as a 4% patch in various brand names such as:
Aspercreme
Lidocare
Salonpas
Prescription-only lidocaine patches come in 5% or 1.8% patches. Zlido is a brand name for a 1.8% lidocaine patch. Five percent lidocaine patches are available generically.
The prescription-only lidocaine patches are approved to relieve long-term nerve pain from shingles in adults.
The safety and effectiveness of lidocaine patches in children are unknown.
Other Forms of Lidocaine
Lidocaine as a local anesthetic is available in several other dosage forms, including:
Cream
Liquid (solution)
Lotion
Spray
Eye gel
Ear drops
Injection
Lidocaine is also available as an acute (short-term) intravenous (into the vein) infusion for abnormal heart rhythm.
How Does a Lidocaine Patch Work?
As a local anesthetic, the lidocaine patch relieves pain in a small area of your body. It does this by blocking the nerves from sending pain signals.
Are Lidocaine Patches Effective?
Several clinical trials suggest that lidocaine patches are effective for relieving chronic (long-term) low back pain.
However, these studies were nonrandomized and didn't include a control group to compare against the treatment group using lidocaine patches. This means the results may be subject to potential biases.
For this reason, there isn't enough evidence to support lidocaine patches' effectiveness in reducing low back pain.
Further high-quality randomized and controlled clinical trials are necessary to study the effectiveness of lidocaine patches for low back pain.
How to Safely Use Lidocaine Patches
In general, keep the following in mind about lidocaine patches:
Don't use lidocaine patches on broken or inflamed (swollen) skin.
Don't apply heat over lidocaine patches like heating pads or electric blankets.
Avoid water on areas applied with lidocaine patches.
Avoid letting lidocaine patches near your eyes to limit severe eye irritation.
Fold the sticky sides of the used lidocaine patches together and safely throw them away to keep them away from children and pets.
Since specific directions might vary per person, use lidocaine patches according to the healthcare provider's recommendations. The following, however, are some typical steps on how to use lidocaine patches:
Clean and dry the affected area before placing the patch.
Apply the patch to the affected area of the body as directed, no more than three to four times per day.
Remove the patch after at most eight hours.
Wash your hands after touching the lidocaine patches.
How Quickly Will a Lidocaine Patch Work?
The amount of lidocaine medication absorbed into the bloodstream will depend on how long the patch is placed on the body and how much of the body is covered with the patch. Repeated use with three patches only once for 12 hours per day, however, doesn't increase the lidocaine level in the bloodstream.
In one study, healthy participants wore three lidocaine patches on their backs for 12 hours on and 12 hours off during a 24-hour period. They had the highest lidocaine level in the bloodstream at 11 hours. Then, at the end of the 24 hours, there was still some lidocaine left in the bloodstream.
People with PHN may start noticing a difference in pain intensity after four hours of using the lidocaine patch.
Experts may suggest using lidocaine patches for four weeks if you experience pain after your shingles rash disappears. However, if you still experience pain after these four weeks, it is recommended to see a pain specialist.
Side Effects and Precautions
Common side effects of lidocaine patches are typically mild skin reactions where the patch is on the body.
These skin reactions are usually temporary and will go away within a few minutes or hours. Examples include:
Abnormal or burning sensation (feeling)
Blisters
Bruises
Irritation
Itchiness
Redness
Skin bumps
Skin color changes
Skin peeling
Swelling
Potentially serious side effects of lidocaine patches may include:
Serious allergic reaction: While a severe allergic reaction to lidocaine is rare, it is possible. Symptoms include breathing problems, itchiness, and rash.
Methemoglobinemia: There are reports of methemoglobinemia with local anesthetics. Methemoglobinemia is a condition that makes it hard for your red blood cells to carry oxygen. So, you may experience symptoms of blue-looking skin, headache, lightheadedness, shortness of breath, abnormal heart rhythm, or seizures.
If you use too many lidocaine patches to cover large parts of your body or use the patches longer than 12 hours within a 24-hour period, side effects may include heart-related effects, such as slow heart rate and low blood pressure. You may also experience the following side effects:
Dizziness or lightheadedness
Drowsiness to unconsciousness
Hot or cold sensation
Mood changes
Numbness
Ringing ears
Seizures
Tremors
Vision changes
Vomiting
Alternative Treatment Options
Other than lidocaine patches, an alternative treatment option is a topical medication called capsaicin, which comes from the capsicum or pepper plant.
Experts recommend capsaicin as first-line and lidocaine patches as second-line treatment if you still experience pain after your shingles rash goes away.
As for low back pain, guidelines are conflicting. According to some experts, there isn't enough evidence to support or rule against the use of topical medications — like lidocaine patches and capsaicin — for low back pain.
Other experts, however, recommend topical capsicum for the short-term treatment of low back pain for up to three months.
Summary
Lidocaine patches are in a drug class called local anesthetics. They work by relieving pain in a small area of your body. It does this by blocking the nerves from sending pain signals.
The Food and Drug Administration (FDA) approved lidocaine patches for relieving postherpetic neuralgia (PHN) pain. However, lidocaine patches are also commonly used for low back pain.
If you're experiencing pain after your shingles rash goes away, experts recommend lidocaine patches as a second-line treatment to capsaicin. People with PHN may feel a difference in pain intensity four hours after using the lidocaine patch. As for lidocaine patches for low back pain, there isn't enough evidence to support or rule against this use.
Read the original article on Verywell Health.
