Kadian Side Effects

  • Generic Name or Active Ingridient: Morphine

General Information

Kadian is an extended-release formula of morphine. Kadian is only for patients already tolerant to opioids; use by others may result in fatal overdose.

Kadian, like all drugs, can cause side effects. Many opioid-tolerant consumers experience no, or minor, side effects from taking Kadian. Most side effects associated with Kadian are not serious and go away on their own with continued use. Some side effects are serious and require the attention of a medical professional.

Abuse and Dependence

One of the more significant side effects associated with Kadian is the high potential for abuse, physical dependence or addiction. The U.S. Drug Enforcement Agency, or DEA, classifies substances according their potential for abuse. The DEA has classified Kadian as a Schedule II narcotic, which means it carries a very high risk for abuse and physical dependence as compared to other legally prescribed drugs.

Being physically dependent on a drug means the individual will suffer withdrawal systems if the amount of the drug in his body were to drop below a certain level. This decrease may be because the user has stopped taking opioids or he has taken a medication to reduce the amount of this drug in his system rapidly.

Kadian withdrawal symptoms include:

  • Abdominal Cramps
  • Agitation
  • Anxiety
  • Blurred Vision
  • Goose Bumps
  • Insomnia
  • Restlessness
  • Seizure
  • Sweating
  • Tremor
  • Vomiting

Adverse Reactions

Do not take Kadian if you are allergic to other opioids, such as morphine or codeine. Stop taking Kadian and seek medical help immediately if you experience symptoms of an allergic reaction, such as hives, rash, itching, difficulty breathing, and tightness in the chest or swelling of the face, mouth, lips, tongue or throat.

The adverse reactions to Kadian are typical of any opioids. Common side effects usually decrease in intensity or stop completely with continued use at proper doses. The most serious side effect is respiratory problems potentially leading to stopped breathing, circulatory depression, dangerously low blood pressure and shock. Physicians should expect side effects, especially in very ill or elderly persons, and treat patients accordingly.

Kadian, like other opioids, may cause dangerous respiratory depression that could be fatal. Respiratory depression is a condition where the lungs do not adequately exchange oxygen and carbon dioxide, characterized by slow or shallow breathing. Physicians treat the effects of respiratory depression with the opioid antagonist, naloxone.

Common Side Effects

The most common side effects associated with this medication are not serious and disappear after taking this drug for a few days. Continue taking this medication but contact the prescribing physician if the following side effects become intolerable or if they do not go away on their own:

  • Constipation
  • Dizziness
  • Drowsiness
  • Headache
  • Lightheadedness
  • Nausea or Vomiting
  • Restlessness
  • Sweating

Serious Side Effects

Some side effects are serious, requiring immediate medical attention. Discontinue Kadian immediately and contact a doctor if you experience serious side effects, including:

  • Agitation
  • Blurred Vision
  • Confusion
  • Disorientation
  • Exaggerated Sense Of Well-Being
  • Fainting
  • Fast, Slow or Irregular Heartbeat
  • Hallucination
  • Mental or Mood Changes
  • Seizures
  • Severe or Persistent Constipation or Stomach Pain
  • Severe or Persistent Drowsiness, Dizziness or Headache
  • Shortness of Breath
  • Slow or Shallow Breathing
  • Sudden Chest Pain
  • Swelling of the Hands, Ankles or Feet
  • Trouble Urinating
  • Unusual Bruising or Bleeding
  • Weakness

By body system

Central Nervous System

The effects of Kadian on the nervous system may be depressive or excitatory; in other words, this opioid may either depress or stimulate the central nervous system, or CNS. Caretakers frequently ignore important symptoms of the excitatory CNS effects of Kadian, attributing side effects to the morphine contained in Kadian.

Patients receiving Kadian may experience muscle spasms or twitching, particularly those individuals with kidney disease. Kadian may cause hyperalgesia, or an increased sensitivity to pain.

Nervous system side effects include drowsiness and sedation. Continuous infusion of Kadian has caused inflammatory masses, some of which resulted in serious neurological problems including paralysis. Other CNS side effects associated with Kadian include seizures, delirium, confusion, tremors, dizziness and muscle twitches.


Kadian consumers have frequently reported respiratory side effects including respiratory depression. Patients with underlying heart or lung disease may experience bronchospasms after taking Kadian.


Kadian may cause gastrointestinal side effects including nausea and vomiting, upset stomach, dry mouth heartburn, obstruction in the intestines and gall bladder problems. Additionally, the morphine in Kadian may worsen gall bladder pain by constricting the common bile duct and causing spasms in one part of the gall bladder.


Cardiovascular side effects include a certain type extreme low blood pressure associated with heart attacks.


Kadian use may cause certain psychiatric side effects including fearfulness, agitation, psychosis, hyper-vigilance, hallucinations and disturbances in thinking.


Kadian may cause urinary retention, or the inability to pass urine, because it contains high doses of morphine. Patients who receive Kadian injections through a catheter or epidural are at special risk for urinary retention. There is an increased risk for urinary infections in patients who use Kadian.

Hematologic and Endocrine

Rarely, patients who take Kadian suffer from a decrease in platelets responsible for blood clots. Endocrine side effects include menstrual problems, including missed periods. Decreased sex drive in men and women have been reported.


Consumers report involuntary muscle activity, including muscle spasms with chronic, high doses of Kadian.

Skin and Eyes

Patients have reported flushing, itching and sweating associated with Kadian. Droperidol may reduce itching for some consumers who use epidural Kadian. Inflammation of the cornea and eyelid have been reported. Visual disturbances and pinpoint pupils are side effects of Kadian; about 26 percent of consumers experience pinpoint pupils after using Kadian.


Kadian may increase liver enzymes in some consumers of Kadian/


Rarely, patients report hypersensitivity and allergic reactions after taking Kadian. Some patients experience warmth after receiving Kadian.