To help control labor pain and stress, an injection of pain
medicine can be given into a vein (intravenous) or into the muscle
(intramuscular). The most common pain medicines used are
opioids. Opioids are also known as narcotics. Examples
of opioids include fentanyl, morphine, and
How opioids work for labor pain
Opioid analgesics suppress your perception of pain and calm your emotional response to pain by reducing the number of pain signals sent by the nervous system and the brain's reaction to those pain signals.
An opioid can help you relax between contractions and decrease the
pain but does not take the pain away completely. Opioids make you drowsy for a
short time and can slow your labor. But opioids are less likely than
epidural anesthesia to cause you to have a forceps or
The most common side effects of opioids include:
Dizziness, lightheadedness, or feeling faint.
Nausea or vomiting.
Opioids are not used when you are close to delivery, because they can
affect a newborn's breathing. They can also make
the baby sleepy and less interested in breast-feeding if they are given close to delivery.
Cunningham FG, et al. (2010). Forceps delivery and
vacuum extraction. In Williams Obstetrics, 23rd ed., pp.
511–526. New York: McGraw-Hill.
How this information was developed to help you make better health decisions.