Pain Channel
Topics & Medications
Related Channels

Demerol Side Effects

Serious Side Effects

Some side effects with Demerol are potentially serious and should be reported immediately to your healthcare provider. These include, but are not limited to:
  • Agitation, disorientation, or hallucinations
  • Shakiness, seizures, muscle twitches, or other abnormal muscle movements
  • A slow heart rate (bradycardia) or fast heart rate (tachycardia)
  • Low blood pressure (hypotension) or high blood pressure (hypertension)
  • Fainting
  • Signs of serotonin syndrome, such as:


    • Confusion or other mental changes
    • A rapid heart rate
    • Nausea
    • Vomiting
    • Diarrhea
    • Hallucinations
    • Blood pressure changes
    • Overactive reflexes
    • Fever
    • Shivering
    • Shakiness
    • Agitation
    • Sweating
    • Seizures
    • Coma


  • The urge to take more Demerol than prescribed or for a non-medical purpose
  • Difficulty passing urine
  • Slow or irregular breathing
  • Chest pain or heart palpitations
  • Signs of an allergic reaction, such as:


    • An unexplained rash
    • Hives
    • Itching
    • Swelling of the mouth or throat
    • Wheezing
    • Difficulty breathing.


Many of the serious side effects of Demerol are due to a toxic metabolite of the medication. This metabolite (known as normeperidine) is a byproduct of Demerol that stays in the body much longer than Demerol itself. If repeated doses of Demerol are taken, normeperidine builds up and can cause serious side effects.
The Top 17 Side Effects of Chemotherapy

Demerol Drug Information

Terms of Use
Advertise with Us
Contact Us
About eMedTV
Privacy Policy
Copyright © 2006-2019 Clinaero, Inc.
eMedTV serves only as an informational resource. This site does not dispense medical advice or advice of any kind. Site users seeking medical advice about their specific situation should consult with their own physician. Click Terms of Use for more information.