An American girl was surprised that her blood turned blue after using an anesthetic cream to treat aching toothache in Rhode Island, the United States, according to the newspaper "The Sun" British.
The newspaper added that the girl woke up and found that she is tired and abnormal color, after using a topical pain reliever, without a prescription, where the drug contains benzocaine, a local anesthetic.
She went to the emergency department of Miriam Hospital in Providence, after her skin and nails looked dark blue, a sign that the body was not getting enough oxygen.
Doctors at the hospital told her she had "methemoglobinemia," which occurs when iron changes in the blood and is no longer able to bind oxygen to carry it throughout the body.
Initial tests showed that the level of oxygen in the girl's blood is low, and when doctors made a more accurate measurement of oxygen, they found that the level in her blood was 67%, a point that can cause tissue damage.
The blood they pulled from the vein took a darker blue appearance as well, and the patient was treated with methylene blue by intravenous injection, where she reported feeling better within minutes.
The medics decided to keep her in hospital overnight for observation before being sent home the next morning and referred to a dentist.