Opioids are sometimes referred to as narcotics. They include morphine and other natural and synthetic chemicals that are similar to morphine in structure. Opioids include:

• Natural opioids
  
  
• • Morphine. Often used before or after surgery to block severe pain. Sometimes referred to as the “gold standard” among opioids, it is the drug against which all others in this class are compared.  However, it is not more effective than other opioids.
    
    
  • Codeine. Usually used to treat pain that is milder than pain treated with morphine.
    
    
• Semisynthetic opioids
  
  
• • Oxycodone. Commonly used alone or in combination with aspirin or acetaminophen.
    
    
  • Hydromorphone. Derived from morphine in the 1920s. It is as effective as morphine and is often better tolerated.
    
    
• Synthetic opioids
  
  
• • Fentanyl. Produces faster onset and shorter duration of pain relief than morphine when its given by injection, but not when given in transdermal or orally disolving forms.
    
    
  • Meperidine. Used less often than some other opioids because it is associated with a higher incidence of side effects. Because of this, its use is generally contraindicated for any type of pain.
    
    
  • Propoxyphene. A relatively weak opioid that provides much less pain relief than other opioids. Therefore its use is not generally recommended.

Other prescribed opioids include hydrocodone, levorphanol, methadone and oxymorphone. There is also an analgesic called tramadol that contains a weak opioid.