Allergic to morphine but what about codeine?

[kristenyale]

(This is my first thread. Hoping this is the correct forum).


When I was younger I had undergone surgery and was given morphine. I had broken out in hives and I believe my throat swelled. I was very young and don't remember the experience. I was told I was having allergic reactions to the morphine.

Ever since then I had never tried morphine so I am not sure if I am still allergic. Is it most likely that I would be allergic to codeine as well? I was thinking about taking only one to see if any allergy symptoms came up.

 

[oar9fi]

If you're allergic to morphine you will most definitely have a reaction to codeine. Codeine is converted to morphine in your body, and it's the morphine that causes the effects. Codeine itself has little or no activity(other than histamine release) if it's not converted to morphine by your liver enzymes.

You can try taking an antihistamine before hand if you must try it. That will most likely help it a bit.

Also, I think everyone is "allergic" to morphine and codeine to some degree because everyone gets itchy from it. But anaphalactic shock is dangerous & potentially fatal if not treated. I hope you have an epi-pen nearby just in case.

 

[Jabberwocky]

as above - yes you'll be allergic to codeine, as codeine is a pro-drug of morphine, meaning codeine gets converted to morphine in the body. while the ENTIRE analgesia of codeine is not dependent just on it being converted to morphine, the majority of its analgesia comes from it. i would advise against it. look into dihydrocodeine - its semi-synthetic and no morphine produced with that.

 

[bunge]

Codeine is just methylated morphine and as stated above will be metabolised into morphine.
Any of the opioids should be ok though. As stated above dihydrocodeine doesnt metabolise into morphine but dihydromorphone so it should be ok and its not to potent for an opiate naive user.
Do an allergy test first though, take a tiny fraction of a dose of your chosen drug, like 1-2mg (obviously how much depends on which drug and its effective dose), wait one hour and if you dont have any symptoms take a small dose, wait another hour and if alls cool you will know your not allergic to that drug.

 

[kristenyale]

Thanks for the replies/help!

I had taken, like Bunge was saying, small portions at a time. No reactions what so ever. I was cautious, however, had an epi-pen just in case.
Not sure if my allergic reaction to any morphine based drug went away over time, but like I said, 0 reactions.

 

[bunge]

Allergies are funny things, they come on suddenly without warning and can happen with substances that you previously had no problem with.
In your case, your allergy episode happened while you were young so its possible for you to lose that allergy with the massive body changes of growing into an adult.
Or the the hospital could have been mistaken about what caused your allergic reaction all those years ago. Who knows? Its pure speculation.lol
Anyway, it sounds like you know what your doing, give it a couple of hours to be sure that theres not a reaction and be sure to have some anti-histamines for minor allergy symptoms (itching, rash, nausea etc alot of people get these so dont panic.lol) and that epi-pen just in case!.

 

[Laid2Rest]

I had no idea codeine did that in your liver. I get itchy as hell taking my vs! Taking a benydryl would take care of it? Ill have to try if so!

 

[Rybee]

I had no idea codeine did that in your liver. I get itchy as hell taking my vs! Taking a benydryl would take care of it? Ill have to try if so!

Aye, when I take 300mg Codeine I itch like hell, if I take 20mg of Cetirizine and 20mg Loratadine it stops the itches completely. Benadryl (Diphenhydramine) will work too. I just choose Cetirizine and Loratadine because they both cost pennies worth.

 

[jeeves]

Everyone here is correct. Codeine is metabolized into morphine in the liver. Diphenhydramine (Benadryl), will definitely reduce the unpleasant histaminergic effects of the codeine. Also, Diphenhydramine has been show to posses CYP2D6 inhibitive qualities, which would reduce the conversion of codeine to morphine. (http://www.ncbi.nlm.nih.gov/pubmed/10824625)
There is little evidence suggesting other OTC antihistamines have similar qualities. Go with Benadryl!

 

[Rybee]

If you don't want to try Codeine, try Dihydrocodeine or Tramadol as these are both semi-synthetic and are not metabolised into Morphine.

Edit: My advice was given on the assumption that you were after management advice, on reflection, I'm not sure whether that's what you were asking?

 

[jeeves]

Rybee gives great advice. Also, you did not specify are you planning on using codeine for pain management or recreation?

 

[PotatoMan]

Administer the codeine. 30mins later, administer the anti-histamine. (For maximum codeine and antihistamine high)

Maybe you just got an acute symptom of the histamine release? Like in a severe way? I'm talking about when you were young of course.