Does codeine make you itchy? If so, why does codeine make you itch? These are common questions. This overview covers what codeine is and why it can make some people itchy.
Article at a Glance:
- Itchiness is a common symptom of codeine use.
- Codeine can make you feel itchy because it triggers a histamine response when it binds to a certain receptor in the central nervous system.
- If prescribed, you may be able to take an antihistamine or switch to another medication if the itching is unbearable for you.
Table of Contents
Itchiness – A Common Opioid Side Effect
Even though codeine is one of the least potent opioids, it does have potentially adverse side effects. Itchiness is a common side effect of codeine and other opioids, affecting roughly 20% to 25% of people who take opioids.
Some of the most common side effects of codeine also include nausea, vomiting, dizziness, feeling lightheaded, feeling drowsy and constipation.
Why Does Codeine Make You Itch?
In the past, researchers believed painkillers made people itch because of how they affect the central nervous system; however, recent research has shown that there is a particular opioid receptor that creates this effect. When this certain receptor is activated following codeine use, it can release inflammatory substances, including histamine.
Codeine and other opioids make your body think that inflammation is occurring because of an allergen. As your body tries to clear itself of the allergen, an allergic-like response (which includes itching) can occur.
People often confuse the itching that occurs with opioids with an allergy, which doctors have started to refer to as a pseudoallergy. Because this certain receptor is activated by codeine and opioids, it can seem very much like an allergic response. This leads to many people being incorrectly identified as having a codeine or opioid allergy when this isn’t actually what’s happening.
Addressing Skin Irritation & Itchiness From Codeine Use
To address the itchiness associated with prescription painkillers, some doctors will give patients antihistamines before giving them these drugs. In other cases, they might change them to a different class of painkillers if it becomes too much for the patient to deal with.
Codeine tends to make people itch even more than stronger opioids for reasons that are currently being evaluated. In some cases, the answer is to have patients take a different type of opioid if they’re having a lot of itchiness while using this drug.
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