Shingles forms a rash or a collection of blisters on your skin due to a viral infection. While a shingles outbreak usually appears as a band across one side of your torso, it can appear anywhere on your body, including your leg and groin.
A 2011 case report noted that your trunk and face are the most common locations for an outbreak, while cases of penile shingles are rare, but can still occur.
Wherever it forms, shingles can also be quite painful or itchy. Treatment with antiviral drugs can usually clear up shingles within a couple of weeks. There are also topical treatments and home remedies that can ease symptoms while the virus disappears.
Because a shingles outbreak has a distinctive appearance, you should be able to distinguish it from other rashes that may stem from allergies, for example. The most effective way to prevent shingles is with a vaccine.
The varicella-zoster virus, which also causes chickenpox, is responsible for shingles. If you’ve had chickenpox, you’re at risk of shingles because the virus can lay dormant in your body for many years after chickenpox clears up.
The shingles virus goes after nerve cells and tends to follow the line of a nerve, which is why it often appears as a band. The large nerves that extend from your spine down your legs are therefore targets for the virus to attack, which could cause the rash to appear on one leg or your groin.
While blistering and a red or discolored rash are the most visible symptoms of shingles, they are often not the first to present. You may experience pain or tingling under your skin a few days before anything appears. In some cases, shingles pain persists with little or no rash developing.
Then, fluid-filled blisters appear. Some burst open and turn crusty. The rash may be itchy and sensitive to the touch. Other symptoms that sometimes occur include:
The typical look of shingles is a blistering rash that often appears on one side of your body, usually covering a relatively small area. If you have that type of rash on one leg or one side of your groin, but not the other, it’s likely to be shingles.
Don’t assume it can’t be shingles just because a shingles rash usually forms on your chest or back or on one side of your face or neck.
A rash on your inner thigh or on your buttocks can be the result of any number of medical conditions, but rashes resulting from something other than shingles tend to look a little different. For example:
- Jock itch appears as a reddish or discolored, half-moon rash that may have small blisters and scaly skin. It may be itchy, but it isn’t painful like shingles. This fungal infection can cause a reaction in areas such as your groin that become moist with sweat, creating an optimal area for the infection to take hold.
- Contact dermatitis is a response to an allergen, such as poison ivy or a chemical in clothing or laundry detergent. It causes a dry, scaly rash, but may also cause hives to appear. Your upper legs and groin area are vulnerable to certain triggers of contact dermatitis, because your skin rubs against clothing.
- Prickly heat or heat rash appears as small red or discolored bumps often where sweat is trapped against your skin. Your legs and groin are common sites for prickly heat, particularly in hot weather.
Antiviral drugs, including acyclovir (Sitavig, Zovirax), valaciclovir (Valtrex), and famciclovir (Famvir) can quickly start fighting the infection and reducing symptoms of a rash, especially if started early. These drugs may also help reduce the risk of shingles complications.
Antibiotics, in oral form and as topical ointments, may also be prescribed to reduce the risk of a bacterial infection developing at the site of the blisters.
To help reduce the pain of shingles, your doctor may prescribe:
- capsaicin topical patch
- tricyclic antidepressants
- numbing agents, such as lidocaine
- corticosteroid injections to reduce inflammation
Home care may include:
- cool baths or showers to ease the pain and clean your skin
- cold, damp compresses to reduce pain and itching
- calamine lotion to reduce itching
The best way to help prevent shingles is to get a vaccine. Shingrix is the primary shingles vaccine available in the United States. Because shingles usually hits when a person is older, people who are 50 years old and above are advised to get the vaccine.
While Shingrix will greatly reduce your chances of developing shingles, it is not 100 percent effective. The vaccine will, however, help reduce the severity of an outbreak if you do develop shingles.
If you suspect shingles, you should call a healthcare professional promptly. Getting started on antiviral medications soon can help reduce your chances of shingles complications, such as postherpetic neuralgia (PHN) — nerve pain that lingers long after the rash clears up.
The Centers for Disease Control and Prevention (CDC) reports that about
If shingles causes an outbreak near your eye, you should get treatment right away. If the infection reaches your eyeball, it can cause scarring and possibly vision loss.
Other rare complications include:
- brain inflammation, or encephalitis
- hearing problems
Even if you’re not sure your rash or blisters are shingles, get checked out. If it’s a fungal infection, for example, you may get a diagnosis and prescription for medication to treat it.
A blistering rash that appears on your leg and groin — particularly if it’s just one side of your body — may very well be shingles, a viral infection that usually needs strong, antiviral medications for proper treatment.
If you experience pain in the area that then develops a rash, it’s probably shingles. The key to avoiding long-term pain and other complications is to get treatment as soon as you notice symptoms.