Skin infection is the most common complication of
chickenpox. Skin infections occur when bacteria from
your skin or under your fingernails get into a chickenpox blister. Sometimes a
skin infection from chickenpox can be serious.
Other complications of chickenpox are rare. They include:
pneumonia. Pneumonia can develop if the chickenpox
virus travels to your lungs. Pneumonia from chickenpox is most common in teens,
adults, and pregnant women who have chickenpox in the last part of pregnancy.
It is also more likely to develop in people who smoke cigarettes, have lifelong
(chronic) lung diseases, or have
impaired immune systems.
Inflammation (swelling) of the brain, known as encephalitis. Encephalitis can develop about 5 to 10 days
after the chickenpox rash appears. In children, encephalitis most often affects a specific part of the brain (cerebellum) and is called acute cerebellar
ataxia. It mainly causes poor muscle coordination, although other symptoms of encephalitis can also occur. In adults, this complication is more likely to affect a bigger part of the brain and cause more severe symptoms. Encephalitis symptoms include confusion, a high fever, a severe headache, sleepiness, sensitivity to light, and nausea. In the most serious cases, a person may have seizures or tremors.
Treatment may include medicine to help relieve symptoms. Some people who have encephalitis may need to stay in the hospital.
Vision loss. Chickenpox virus that spreads into the clear
eye covering (cornea) can leave scars that can cause vision
Reye syndrome. Reye syndrome can develop in young
people who take aspirin during chickenpox or flu treatment. It can be prevented
by not giving aspirin to anyone under the age of 20.
of the joints (arthritis). Sometimes people with chickenpox have pain
in their muscles and joints. This pain usually lasts as long as the chickenpox
rash. Medicines taken for fever or other general illness often help ease the
The following complications of chickenpox are very rare:
Inflammation of the nerves of the eye (optic
neuritis) or the spinal cord.
Inflammation of the tissues surrounding the brain and spinal cord (meningitis).
Nerve damage that causes problems
with movement of the face or other parts of the body.
disorders, such as a decrease in the number of blood cells that help clot blood
Women who are pregnant when they have chickenpox are at risk for
complications such as premature labor or varicella pneumonia, and the fetus is
at risk of developing chickenpox. Fetuses with chickenpox are more likely to
develop birth defects or other complications before and after birth. Newborn
babies can also get chickenpox when their mother has the illness within a few
days of delivery.
Primary Medical Reviewer
John Pope, MD - Pediatrics
Specialist Medical Reviewer
Thomas Emmett Francoeur, MD, MDCM, CSPQ, FRCPC - Pediatrics
How this information was developed to help you make better health decisions.