codeine + loratadine

[Tortoise]

Hello kids

I am writing a novel and one of the characters in my novel is planning to take a moderate dose of codeine. Only thing is, he recently took some loratadine for his hay-fever and i would like to know if I need to be aware of any dangerous effects of combining these two drugs. I seem to recall reading that non-drowsy histamines and codeine shouldn't be mixed. For the sake of fictional validity could somebody please tell me if this is true or not?

Thanks

[darkglobe]

The outcome of your novel would depend on a few factors. This is what you characters should know:

1. How recent is "recently"?
If the loratadine was taken within the last few days, you'd be safer leaving the Codeine alone.

2. The dosage of Loratadine/Intended Codeine dosage
Common sense really. The higher the dose(s), the higher the risk. ALthough it's not a totally linear correlation, and sometimes people get what is scientifically known as "shit luck".

3. Other
Seeing as I've never heard of Loratadine before, don't take my word as Gospel, but I assume it's probably a newer-generation of non-drowsy antihistamine similar to Acrivastine (which is in UK Benadryl hayfever pills).
I'm not sure about drug interactions with non-drowsy anithistamines, but I do remember reading that Dextromethorphan and non-drowsies should not be mixed, so maybe they are just generally quite "picky" substances when it comes to drug interactions.

I don't mean to hijack your thread, as your novel seems a good idea (ha), but I would be interested to learn more in this case.

[merc11292]

im nearly positive theres no drug interaction with loratadine (claritin)and codeine. However there is one between Diphenhydramine (benadryl) and codeine, Diphenhydramine increases the effects of opiates in general, including codeine.

[Tortoise]

Diphenhydramine and Dimenhydrinate both increase the sedation of codeine but not the euphoria. Swim nearly always uses 1 50mg tablet of Dimenhydrinate 1/2 hour before taking high doses of codeine (~300mg or more) to reduce the itchiness and intensify the 'nod'. It really smooths out the experience for him.

[Paracelsus]

Originally Posted by darkglobe

I'm not sure about drug interactions with non-drowsy anithistamines, but I do remember reading that Dextromethorphan and non-drowsies should not be mixed, so maybe they are just generally quite "picky" substances when it comes to drug interactions.

Actually, only two 'non-drowsies' are dangerous when mixed with DXM. Both are withdrawn from the market. They are terfenadine and astemizole. I created a thread on this, look it up if you want.

I don't see any dangers in a combo of loratadine and codeine, but I could totally miss something.

[darkglobe]

Thanks for that, Paracelsus. I only mentioned it as I read it in William White's FAQ, which is where I learnt about Dextromethorphan.

And the list of things not to take with my mum's Benadryl (Acrivastine) is huuuuge.