High Doses of N-Acetyl-P-Aminophenol Cause Acute Changes in Electroencephalographic and Electrocardiographic Activities in Wistar Rats.

N-acetyl-p-aminophenol (APAP), or acetaminophen, is the most prescribed analgesic and antipyretic, even used in association with other drugs. Because it is easily bought in drugstores, much evidence about its toxic effects is known due to high doses or continuous use, which can lead to death in cases of intoxication. The present study aimed demonstrate the ability of APAP to change the brain and heart electrical activities, as early as significant increase in liver enzymes. Thus, a toxic dose of 1 g/kg was administered orally, and the animals were assessed every 3 h until 12 h for electroencephalography, electrocardiography and liver function data. The results showed that a toxic dose of APAP was capable of reducing brain electrical activity for the delta, theta, beta and gamma waves; however, the alpha wave activity was increased. In the heart, a reduced electrical activity was observed synchronously with the electroencephalogram. During the 12-h follow-up period, a significant increase in liver enzymes was observed. Taken together, we conclude that high doses of APAP can alter frequency brain oscillations and promote cardiac changes independently of liver damage in the first 12 h.