Managing Pain Medication Side Effects

Managing Pain Medication Side Effects

MSK pharmacist Stacy Wong

MSK pharmacists can help patients manage their pain. Pictured here: Stacy Wong

The side effects of opioids and other pain medications have been well studied and can be managed effectively. Many of the common side effects of pain medicines are also symptoms of other conditions, including the underlying cancer. That’s why an interdisciplinary approach to symptom management is important.

Common side effects of opioids and other pain medications include the following:


This common side effect of opioids can often be lessened. An increase in fluids, an increase in dietary fiber (if your condition permits), and moderate exercise (with the advice of your doctor or nurse) can all have an effect. Laxatives or stool softeners can usually help constipation.


Nausea and vomiting sometimes occur in the first day or two of taking an opioid medication. Report any nausea or vomiting to a nurse or doctor. They can prescribe antinausea therapies to control these side effects.

Sedation, Drowsiness, or Clouded Thinking

Sometimes opioids can cause sedation, drowsiness, or sleepiness for the first day or so or after a dose is increased. Some people find that they become confused, disoriented, or simply absentminded after receiving a medication for pain relief. If such effects become pronounced, tell a doctor immediately. The dose can be adjusted, another drug can be prescribed, or another drug can be added.

Slowed Breathing

Opioids can slow breathing, particularly at high doses. The condition usually resolves as the body gets used to the medication. We monitor respiration and other vital signs closely throughout each individual’s hospital stay. Still, the cancer care team should be told if slowed breathing becomes uncomfortable or is otherwise troublesome. Additional drugs can be prescribed to treat this side effect.