Hives usually are caused by other things besides infection, although it could be from a virus. It could be from an allergen, or some sort of an allergy that you have. It could be from a hormonal change. And it even could be emotional in some situations.
Caused by an allergic reaction to medications or food, hives can be a sign of a life-threatening problem when accompanied by difficulty breathing and a drop in blood pressure. Rashes can develop from an allergy to a medication, also known as DRESS syndrome (drug reaction with eosinophilia and systemic symptoms).
Acute hives are often an allergic reaction to something you put into your body, like food, drink or medication, or something that you touch. The skin has immune cells called mast cells. When these cells go into action, they release chemicals, including one called histamine. Histamine is the reason that hives form.
Seek emergency medical care. Chronic hives do not put you at sudden risk of a serious allergic reaction (anaphylaxis). If you get hives as part of a severe allergic reaction, seek emergency care. Symptoms of anaphylaxis include dizziness, trouble breathing, and swelling of the tongue, lips, mouth or throat.
Stress hives can look a little like bug bites: both are red, puffy, and itchy, and may appear initially as individual bumps, says Stevenson. However, hives are more often irregular in shape and can join together in larger patches, especially if you scratch them.
Viral infections are the main cause of hives in children. Influenza, mononucleosis (“mono”), RSV (respiratory syncytial virus), the common cold, urinary tract infections, and many other viruses can cause hives in children and adults. We now know that COVID-19 is also a virus that causes hives in some patients.
If you have a case of hives that lasts for more than a few days, it's time to call the doctor. Sometimes, but not always, hives occur as part of a more serious allergic reaction called anaphylactic shock. Seek medical attention right away if you experience hives along with: Dizziness.
Likewise, urticaria can be associated with malignant neoplasms such as lymphoma, leukemia and ovarian carcinoma[28].
Leukemia may cause a skin rash that looks like red, brown, or purple little dots, and sometimes may resemble bruises. These result from burst capillaries and may be an early sign of the condition. In advanced leukemia stages, skin rashes may look like bumps, nodules, blisters, or ulcers.
If a person has hives, they have a risk of developing a life threatening condition called anaphylaxis. Being aware of other symptoms of this condition, such as swelling of the face, tongue, or throat, a rapid heartbeat, or lightheadedness is important.
Viral Infection.
The most common cause of hives all over the body is viral infections. Research has confirmed this. Other symptoms such as a fever, cough or diarrhea are also present. The hives may last 3 days.
Apply a cold compress, such as ice cubes wrapped in a washcloth, to the itchy skin several times a day—unless cold triggers your hives. Use anti-itch medication that you can buy without a prescription, such as an antihistamine or calamine lotion.
Studies show that 30-40 percent of cases of chronic hives may be the result of an underlying disease, such as an autoimmune disease. But experts also believe that some cases of chronic hives develop from the body's own immune defenses.
You can get a rash when you're stressed — stress and anxiety can cause hives. For this reason, sometimes hives might be called “stress hives” or a “stress rash.”
Stress rashes often appear as raised red bumps called hives. They can affect any part of the body, but often a stress rash is on the face, neck, chest or arms. Hives may range from tiny dots to large welts and may form in clusters.
Hives and itching often worsen at night because that's when the body's natural anti-itch chemicals are at their lowest.
The most common autoimmune conditions seen with hives include thyroid disease, rheumatoid arthritis, and Type 1 diabetes. You can also experience hives if you have lupus, vasculitis, and liver diseases. If you have an autoimmune condition, you usually have other symptoms in addition to hives.
Many people with lupus experience a red or purplish rash that extends from the bridge of the nose over to the cheeks in a shape that resembles that of a butterfly. The rash may be smooth, or it may have a scaly or bumpy texture. It can look like a sunburn. The medical term for this type of rash is a malar rash.
Lupus can cause hives, but this is uncommon. The exact cause of hives in lupus isn't clear. But it may be due to certain antibodies produced by some people with lupus. Sun exposure also may play a role.