What are side effects of opioid medication?

Dr. Howard J. Shaffer, PhD
Addiction Medicine Specialist

In addition to their powerful painkilling effects, opioids can produce a feeling of well-being and euphoria. They also cause drowsiness and, among novice users, can cause nausea and vomiting. With repeated use, these drugs commonly cause constipation.

Dr. Travis M. Hendry, MD
Orthopedic Surgeon

Side effects of opioid medication can include:

  • Constipation, the most common side effect
  • Decreased breathing, the most serious side effect
  • Sleepiness, tiredness, and/or dizziness
  • Itching and/or sweating
  • Nausea, vomiting, and/or dry mouth
  • Slower reactions (physical and mental) that can reduce alertness or judgment
  • Depression, feeling generally "low," feeling "high," and/or seeing or hearing things that aren't there
  • Difficulty urinating
  • Low levels of testosterone (a hormone); low levels can result in lower sex drive, energy, strength, or bone mass
  • Altered taste, vision, heart rate, and/or blood pressure
  • Shaking and/or twitching
  • Becoming more sensitive to pain
Donna Hill Howes, RN
Family Practitioner

Side effects may include sleepiness, dizziness, problems with thinking or coordination, nausea, vomiting, constipation, trouble urinating, rashes, sweating, flushing, itching, depression, and breathing problems. The effects of opioids are often stronger in older people.

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Dr. Scott D. Martin, MD
Orthopedic Surgeon

Possible side effects of opioid medications include nausea, dizziness or lightheadedness, vomiting, euphoria, constipation, abdominal pain, rash, headache. It may be habit-forming when taken over time in large doses. Opioids should be used cautiously by people with peptic ulcers, blood-clotting disorders, and liver disease. Opioids can cause convulsions.

Dr. David Kuhl
Hospice & Palliative Medicine Specialist

Common side effects from opioids are constipation, nausea, vomiting and drowsiness. Some people also experience confusion and, on high doses, muscle twitching (myoclonus).

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.