What Is Codeine? - Effects & Withdrawal

Instructor: Danielle Haak

Danielle has a PhD in Natural Resource Sciences and a MSc in Biological Sciences

Codeine is a narcotic pain medication used to treat mild to moderate pain. Prolonged use can cause both mental and physical dependence, so dosages should be controlled by a doctor. Read this lesson to learn more.

What Is Codeine?

Codeine is a narcotic pain reliever used to manage mild to moderate pain levels and is similar to morphine and hydrocodone. It can also be used to help suppress coughing. Codeine will treat symptoms but does nothing to treat the cause of pain or coughing. It's usually taken orally, as a pill or liquid, and it may be mixed with additional pain relievers (like Tylenol). The body naturally converts some of the codeine to morphine, so following the prescribed dosage (both amount and frequency) is important.

Codeine is usually taken orally, as a tablet or a liquid.

Side Effects of Codeine

There are a number of commonly reported side effects of codeine, including mental and physical dependence if taken for a prolonged period. Let's take a look at some of them.

  • Can slow or stop breathing
  • Drowsiness
  • Feelings of relaxation or calmness
  • Lightheadedness
  • Dizziness
  • Shortness of breath
  • Nausea
  • Vomiting
  • Constipation
  • Sweating
  • Headache
  • Mood changes
  • Difficulty urinating

Some additional, but more serious side effects occur more rarely and require immediate medical attention. These include:

  • Allergic reactions, including rash, itching, hives, trouble breathing
  • Difficulty swallowing
  • Irregular heart rate
  • Seizures
  • Impaired vision

Elderly patients and people with existing breathing conditions are particularly susceptible to experiencing respiratory depression when taking codeine. This means breathing slows so much that the body stops getting adequate oxygen and carbon dioxide accumulates.

Codeine has also been known to kill children if they are given codeine following a tonsillectomy or adenoid removal.

If too much codeine is consumed, a person can overdose on it. Symptoms of overdose include bluish coloration of the skin or lips, chest pains, fainting, extreme drowsiness or loss of consciousness, slow or irregular heart rate, and irregularly small pupils.

Possible Interactions

Codeine shouldn't be used by people with existing breathing conditions or uncontrolled asthma due to its ability to depress breathing even further. It also should not be taken by anyone who experiences frequent bouts of hyperventilation. Codeine also affects the gastrointestinal system and shouldn't be taken by people with a type of bowel obstruction called paralytic ileus. Finally, codeine's effects may be amplified when combined with alcohol or other sedatives.

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