Always read the label before taking any drug. It will list ingredients and common side effects.
Acetaminophen is often combined with other drugs. Excedrin, for example, is acetaminophen, aspirin and caffeine. Many cough and cold medications are also combinations of acetaminophen and other drugs. The risk of overdose is high if you do not read the labels.
NSAIDS are generally safe to treat occasional acute pain or inflammation, and acetaminophen is generally safe for pain, as long as you follow directions. Use the one that works best for you. For chronic conditions, consult with a doctor to find the best treatment for you.
Note: Information based largely on PDRHealth.com.