JWilburn asked
I am itching after taking hydrocodone. Can I take Allegra or Claritin to help with the itching?
Answer
Yes, antihistamines such as Allegra (fexofenadine) and Claritin (loratadine) can safely be used with hydrocodone to help symptoms of itching if they occur. Sometimes, more sedating antihistamines like Benadryl are more effective for itching reactions to hydrocodone as they have stronger anticholinergic effects.
Why Does Hydrocodone Cause Itching?
If you are experiencing side effects from your hydrocodone, it may be because you have what is known as a pseudoallergy. In fact, many side effects of opioids, not just hydrocodone, are classified as pseudoallergies, which often get misclassified as "true" allergies according to various studies. They not considered true allergies because they are not immune mediated. Pseudoallergies are due to histamine release, causing symptoms such as:
- Hives
- Itching
- Skin Redness
- Flushing
- Sweating
Also, more serious side effects such as low blood pressure and increased heart rate can be classified as pseudoallergic symptoms, but may also indicate a true allergy.
What To Do If Hydrocodone Causes Itching?
If hydrocodone is causing you to itch, you have a few options:
- Take an antihistamine at the same time as the hydrocodone. Traditional antihistamines (i.e. H1-blockers) have good evidence that they can reduce histamine binding and therefore decrease symptoms such as itching and hives. Over the counter antihistamine options include:
- Benadryl (diphenhydramine)
- Allegra (fexofenadine)
- Claritin (loratadine)
- Chlor-Trimeton (chlorpheniramine)
- Zyrtec (cetirizine)
- Xyzal (levocetirizine)
- H2 blockers, such as Pepcid (famotidine), Tagamet (cimetidine) and Zantac (ranitidine), although traditionally used to reduce stomach acid and relieve indigestion, have also been shown relieve symptoms of itching in certain cases.
- If an antihistamine isn't helping to reduce symptoms of itching, a dose reduction of hydrocodone will most likely cause less itching.
- Lastly, a change in drug to a non-opioid, such as ibuprofen, naproxen or acetaminophen, may be prudent if the itching is too bothersome.
Summary
- Hydrocodone, and all opioids, can cause itching, which are often classified as a pseudoallergy.
- Pseudoallergy symptoms are caused by histamine release and are not classified as "true" allergies as they are not immune mediated.
- Antihistamines can help relieve symptoms or a dose/drug change may be necessary if symptoms are too severe.
