Acetphenetidin is a compound popularly known as phenacetin and is a painkiller and fever reducer. It is most commonly used in the treatment of headaches, toothaches, and menstrual cramps. Though phenacetin is widely used, prolonged use can lead to kidney failure, methemoglobinemia, and cancer. Because of these health concerns, several synonyms of acetphenetidin have been developed and widely used. These synonyms include some common painkillers like paracetamol, acetaminophen, APAP, or Tylenol. These compounds have similar analgesic properties as phenacetin but have proven to be much safer and with less adverse effects. Therefore, people are advised to use these alternative painkillers instead of phenacetin.