Constipation is the most common side effect from opioid medications, and dealing with the issue can be frustrating. Farshad Ahadian, MD, the medical director of UC San Diego Health’s Center for Pain Medicine, answers common questions he hears from his patients about treating opioid-induced constipation (OIC). 1. Q: Why do opioids cause constipation? A: Opioids work by activating small proteins all over the body, called receptors. When opioids activate the receptors in the spinal cord, this relieves pain. But when opioids activate the receptors in the gut, everything in the GI system is slowed down and impaired. 2. Q: Who is at higher risk of experiencing OIC? A: OIC affects anywhere from 15 to 90% of patients taking opioids. The likelihood of constipation increases with higher doses of opioids and longer durations of therapy. More women than men experience OIC, and it’s also more likely to affect older people, which is unfortunate, since my elderly patients tend to have a lot of chronic pain conditions. They really need the pain relief but find they can’t tolerate the medications due to side effects. My heart goes out to them and we work together to try to find a solution. 3. Q: Can OIC be treated? A: Absolutely. The best way to avoid OIC is to avoid opioids. Patients should take full advantage of the wide array of non-narcotic treatment options for pain such as physical rehabilitation, interventional pain therapies, and complementary and alternative therapies that are now available to help reduce or eliminate the need for long-term opioid therapy. If patients require opioid therapy, we can create a preventive regimen with laxatives and stool softeners to block or lessen the impact of OIC. In severe and intractable cases where other options have failed, peripherally selective opioid antagonists now provide a new treatment option for severe OIC. These medications include naloxegol (Movantik) and methylnaltrexone (Relistor), and they work to block the effects of opioids on the receptors in the gut. 4. Q: As a physician, what’s the hardest part of treating OIC for you? A: OIC is sometimes difficult to treat because patients are reluctant to report it to their doctors. I encourage all patients to talk to their doctors if they’re experiencing OIC, because this condition can lead to a significant reduction in quality of life, functional status, and even cause patients to stop taking their pain medications. OIC can be treated effectively with the right strategies, so it’s important to discuss it with your doctor.