Endometriosis is a disease in which endometrial-like tissue or tissue that resembles uterine lining begins to grow elsewhere and form lesions. These lesions respond to the hormonal cycle of menstruation by swelling and shedding each cycle. But because the lesions are located outside the uterus, they cannot shed properly, which results in inflammation, severe pain, and infertility.

Several approaches can be used to treat the pain caused by endometriosis, and many hospitals have specialized pain clinics to provide advice and support for patients with endometriosis-associated pain, and those with other chronic pain conditions. One option is opioid-based pain relievers, sometimes called narcotic analgesics.

What are opioid narcotics?

Opioid narcotics are treatments that affect the opioid receptors in the brain that perceive pain. These chemicals bind to the opioid receptor, and, in the process, change the sensitivity of nerve cells to pain, meaning that the brain does not receive the message of pain as strongly. Opioid narcotics include hydrocodone, oxycodone, codeine, and hydromorphone.

Opioid narcotics research for endometriosis

A study in an animal model of endometriosis, published in the journal Reproductive Sciences, suggested that endometriosis may cause a shift in the prevalence of opioid receptors, which may indicate that the way these patients experience pain and the effectiveness of opioids may be very different for endometriosis compared with other chronic pain conditions.

Another study, published in Obstetrics & Gynecology, performed a survey among obstetricians and gynecologists to determine how and which opioid narcotics are prescribed for various conditions. While many health professionals prescribe opioid narcotics for endometriosis, there is not a consensus about which ones may be more effective for treating the disease. The study indicated a need for best prescribing practices for endometriosis and other conditions.

Warnings and side-effects

Opioid narcotics are highly addictive and should not be used long term. They can also cause side effects including nausea, constipation, drowsiness, headache, dizziness, and confusion or impaired judgment.


Endometriosis News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.