Codeine linctus is a cough medicine that is only available overseas. Its primary ingredient, codeine phosphate, is a Schedule II controlled substance in the U.S.

Article at a Glance:

  • Codeine linctus is a codeine formulation that is available overseas but not in the United States.
  • It is used to treat cough.
  • Like other codeine products, codeine linctus can be habit-forming and can lead to addiction or overdose.

What Is Codeine Linctus?

Codeine linctus is a cough medicine available in places like the U.K. and Australia. The codeine linctus active ingredient is codeine phosphate. Although codeine linctus is not available in the United States, codeine phosphate is a Schedule II controlled substance in the U.S.

Codeine linctus works when someone’s central nervous system is overstimulated and leads them to feel like they need to cough. The reflex is blocked when the cough has no purpose (for example, you’re coughing because of overstimulation and not because you need to clear phlegm). The urge to cough occurs in your brain, specifically the brainstem. Opioids like codeine block this urge by working on mu and kappa opioid receptors in the brainstem.

Codeine linctus comes in a clear oral liquid.

Codeine Linctus Side Effects

Codeine linctus’s side effects include:

  • Mood changes
  • Confusion
  • Dizziness
  • Drowsiness
  • Rapid or slow heartbeat
  • Low blood pressure
  • Slowed breathing
  • Nausea or vomiting

Codeine Linctus High

Codeine linctus can get you high because of the codeine. A high is particularly likely if someone takes larger doses of this drug. Codeine linctus is one of the less potent opioids, so the high wouldn’t be as significant as what a person might feel with other opioid prescription drugs.

Some people are genetically more likely to get high on codeine linctus than other people, due to an enzyme in the liver called CYP2D6. This enzyme breaks codeine down into morphine faster in some people than in others. This can lead to codeine taking effect more quickly than expected, leading to a high or an overdose in some cases.

Codeine Linctus Dose

General codeine linctus dose guidelines include the following:

  • For cough in adults, the recommended dose is 15 mg (there are 15 mg in every 5 ml of the drug) every four hours, up to a max of four doses per day.
  • No codeine linctus dose is recommended for children because this drug has the risk of breathing problems and other complications.
  • A reduced dose may be needed in older individuals.

Codeine Drug Warning

Codeine linctus can be habit-forming. For this reason, it is important to follow your doctor’s instructions for taking codeine linctus. Certain people are advised against taking it altogether, including those who:

  • Are addicted to opioids
  • Have liver problems
  • Have breathing problems, like slowed breathing or an acute asthma attack
  • Have serious bowel problems like paralytic ileus
  • Have increased pressure in their brains or a head injury
  • Break codeine down into morphine more quickly than expected
  • Are under the age of 18 years
  • Are breastfeeding

What Is Codeine?

Codeine is an opioid pain reliever narcotic.  It is a controlled substance in the U.S. and many other countries. Codeine is a natural opioid, meaning that it is derived from morphine and is not chemically man-made. It is considered one of the milder opioids available: one milligram of codeine equates to roughly 0.15 milligrams of morphine.

How Does Codeine Work?

When you take codeine, your liver breaks it down into morphine. Then, it crosses into your brain and binds to opioid receptors. Opioid receptors can alter how you feel pain and reduce the urge to cough.

Opioids like codeine slow the function of the central nervous system, which can include essential functions like respiration. If you take too much of an opioid, it can slow your respiration to the point that you overdose or stop breathing altogether, which is one of the biggest risks of these drugs.

Are There Any Risks to Taking Codeine?

Other risks of codeine-based products include physical dependence and addiction. With a physical dependence on codeine, a person has used the drug for a period of time until their body feels like it needs codeine to function normally. Then, if someone were to stop taking it suddenly after developing a tolerance, they would go through withdrawal symptoms.

Codeine and other opioids are so addictive because they trigger a release of dopamine and feel-good neurotransmitters when they enter the brain. This then starts a cycle of addiction: your brain compels you to continue seeking out whatever it was that released the brain chemicals that felt pleasurable, over and over despite negative consequences.

If you or your loved one is struggling with codeine addiction, help is available. Addiction experts at The Recovery Village can create a personalized treatment plan that addresses your unique situation, including any co-occurring mental health issues you may be facing. Contact our helpful representatives to discuss your treatment options, answer your questions about treatment and start you on the path to a healthier, opioid-free life.

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Editor – Melissa Carmona
Melissa Carmona puts years of writing and editing experience to work helping people understand substance abuse, addiction and mental health disorders. Read more
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Medically Reviewed By – Dr. Jessica Pyhtila, PharmD
Dr. Jessica Pyhtila is a Clinical Pharmacy Specialist based in Baltimore, Maryland with practice sites in inpatient palliative care and outpatient primary care at the Department of Veteran Affairs. Read more

Australian Government Department of Health. “Codeine Linctus.” Healthdirect. Accessed July 3, 2021.

Marks, Sean; Rosielle, Drew A. “Opioids for Cough.” Palliative Care Network of Wisconsin. Accessed July 3, 2021.

U.S. Department of Justice, Drug Enforcement Administration. “Conversion Factors for Controlled Substances,” April 2021. Accessed July 3, 2021.

Electronic Medicines Compendium (EMC). “Codeine Linctus BP.” November 14, 2018. Accessed July 3, 2021.

U.S. Food and Drug Administration. “Use of Codeine and Tramadol Products in […]uestions and Answers.” August 1, 2019. Accessed July 3, 2021.

American Academy of Family Physicians. “Opioid Conversion Table.” Accessed July 3, 2021.

Centers for Disease Control and Prevention. “Commonly Used Terms.” January 26, 2021. Accessed July 3, 2021.

Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.