The research, published in the journal Addictive Behaviours, involved 150 patients.
Previous studies have shown that nearly two-thirds of patients receiving medication-assisted treatment for opioid addiction also have chronic pain and many experience depression.
About 67 per cent of the patients surveyed by researchers said they had used marijuana in the past month.
"Some are admitting they use it just for recreation purposes, but a large number are saying they use it to help with pain, sleep, and their mood," said Marian Wilson, from the Washington State University in the US.
The study noted that opioid overdose rates have more than tripled in the past two decades and are now the second-leading cause of accidental death in the US.
Patients believe using marijuana helps them with their symptoms, but the study's results could indicate the opposite is true for those in addiction treatment - that by strengthening the connection between feelings of pain and emotional distress, it makes it harder for them to manage their symptoms.
Disclaimer: No Business Standard Journalist was involved in creation of this content