A few nonspecific symptoms may persist for years before other problems develop.

Selenium is an essential element, but ingestion of more than 5 mg/day leads to nonspecific symptoms.

About 20 percent of infected people experience mild nonspecific symptoms that resemble influenza, making diagnosis difficult without a blood test.

Other nonspecific symptoms can include headache, conjunctivitis, slight photophobia and partial loss of taste.

Children often exhibit only nonspecific symptoms, such as irritability and drowsiness.

Dr. Thomas chose people with nonspecific symptoms that tend to improve without any medical intervention.

"These are nonspecific symptoms that many people have," he added.

It is acutely toxic, causing a variety of nonspecific symptoms.

It is commonly identified on blood tests performed either for screening or to evaluate nonspecific symptoms.

Infants usually show nonspecific symptoms, including anorexia, diarrhea, or irritability.