Both shingles and poison ivy cause a painful, blistering rash. Poison ivy is an allergic reaction, while shingles is a viral infection. Shingles also causes additional symptoms that can differentiate the conditions.
The varicella-zoster virus causes chickenpox. After a person has chickenpox, the virus travels from the skin to the nerves and remains dormant.
Sometimes, the virus reactivates and travels from the nerves to the skin, causing shingles, and resulting in a painful, blistering rash.
Poison ivy is allergic contact dermatitis that can cause a painful, blistering rash. The rash is an allergic reaction to urushiol oil, which is present in poison ivy, oak, and sumac sap.
Poison ivy rashes are one of the most common types of allergic contact dermatitis.
The following table outlines the differences between shingles and poison ivy:
| Shingles | Poison ivy | |
|---|---|---|
| Cause | varicella-zoster virus | direct contact with the plant |
| Characteristics | • a painful blistering rash that typically develops on • blisters tend to be small and develop in clumps | • a painful rash that develops anywhere skin comes into contact with the plant • some people develop black spots or streaks instead of a rash, but this is rare |
| Additional symptoms | • fever • chills • headache • nerve pain • upset stomach | no additional symptoms |
| Treatment | • prescription antiviral medication • calamine lotion • colloidal oatmeal baths • cool compresses | • antihistamines • calamine lotion • short, lukewarm baths • hydrocortisone cream • pain medication |
| Prevention | getting the shingles vaccine (the | • wearing long sleeves and pants when in areas of poison ivy • applying a poison ivy blocker to the skin • washing skin, clothes, and tools after being near poison ivy |
Shingles and poison ivy rashes are both characterized by itchy, painful blisters, but some key differences distinguish them.
One difference is where the rash appears. The American Academy of Dermatology (AAD) explains that while a shingles rash can develop anywhere on the body, it is most common around the trunk. It typically affects just one side of the body.
The
The
According to the AAD, it can take 2–3 weeks for the rash to appear if a person has not come into contact with the plant. This can make it challenging to identify the cause of the rash.
Poison ivy does not usually cause additional symptoms.
The table below shows what symptoms to look for to help determine the cause of the rash:
| Shingles | Poison ivy | |
|---|---|---|
| Red, dark, or skin-colored blotches | ✓ | ✓ |
| Itching | ✓ | ✓ |
| Blisters | ✓ | ✓ |
| Burning feeling | ✓ | |
| Nerve pain | ✓ | |
| Headache | ✓ | |
| Fever | ✓ | |
| Fatigue | ✓ | |
| Chills | ✓ |
Both shingles and poison ivy rashes look similar and follow a similar pattern. Anyone with a blistering skin rash should contact a doctor immediately.
Shingles
The AAD notes that a shingles rash develops in the following way:
- A few days before the rash develops, a person will experience a painful, burning sensation on the area of the skin where the rash will appear.
- The rash will appear. It typically develops on only one side of the body, and small blisters will develop in clumps.
- The blisters will break open and crust over. It can take 2–4 weeks to clear completely.
Learn more about what a shingles rash looks like.
Poison ivy
Poison ivy rashes can occur anytime a person comes into contact with the plants. The AAD explains that the first time a person comes into contact, a rash can appear in 2–3 weeks.
After the first contact, poison ivy rashes usually appear within a few hours.
The rash develops in the following way:
- Before the rash appears, the skin will itch intensely. It can be intense enough to wake up a person at night.
- An itchy, painful, blistering rash appears. The blisters can break open and leak.
- The blisters crust over. The rash usually resolves in 2–3 weeks.
Occasionally, people develop black spots or lines on their skin. Doctors call this black-spot poison ivy dermatitis.
Learn more about what a poison ivy rash looks like.
People with shingles can also develop:
- fever
- chills
- upset stomach
- headache
- nerve pain
Although poison ivy does not usually cause additional symptoms, a person who has come into contact with the plant can develop a severe allergic reaction. This can cause:
- difficulty swallowing or breathing
- rash around the eyes, mouth, and on the genitals
- facial swelling
- fever
- rashes that cover most of the body
Emergency medical attention is necessary if a person develops any of the above symptoms.
The following can help treat the rashes associated with poison ivy and shingles.
Shingles
Doctors can treat shingles with antiviral medications, including:
- acyclovir
- valacyclovir
- famciclovir
These medications are most effective when a person takes them within 3 days of the rash appearing. While they do not cure the illness, they may shorten the duration and severity of the infection and ease the pain.
People can also try:
- taking over-the-counter pain medications
- applying cool compresses
- applying calamine lotion
- taking colloidal oatmeal baths
Poison ivy
For poison ivy, the AAD recommends washing the skin in lukewarm, soapy water as soon as possible after exposure to remove the urushiol oil.
Urushiol oil can stick to surfaces, including pet fur, gardening tools, and clothing, so it is essential to wash all of these thoroughly to remove all traces of the oil.
To help relieve the itch, a person can:
- take short, lukewarm baths
- use calamine lotion
- apply hydrocortisone cream
- take antihistamine pills
Optum Perks is owned by RVO Health. By clicking on this link, we may receive a commission. Learn more.
Besides poison ivy or shingles, a rash may stem from other causes, such as:
- allergic reactions such as to food or household products
- bacterial, viral, or fungal infections
- underlying conditions
- bites and stings from insects
The
The
While pets are not usually sensitive to poison ivy, fur can trap urushiol oil. Anyone petting them may transfer the oil to their skin and clothing.
If a pet has come into contact with poison ivy, the FDA suggests bathing them while wearing gloves.
What is the primary way to tell the difference between shingles and poison ivy?
The location of the rash and accompanying symptoms, such as flu, can help distinguish between shingles and poison ivy.
How can a person rule out shingles?
If someone thinks they may have shingles, they should visit a healthcare professional for a test to confirm the diagnosis.
What are the first signs of poison ivy?
The first signs of poison ivy include developing a painful rash where the plant has touched the skin.
Shingles and poison ivy cause painful skin rashes, but their causes differ. Shingles is a viral infection, while poison ivy is allergic contact dermatitis.
Although the rashes look similar, people with shingles usually experience additional symptoms, including fever, headaches, chills, and nerve pain.
Anyone with shingles should contact a doctor as soon as possible. Prompt treatment with antiviral medications may reduce the severity and length of infection.