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Taking 1st gen and 2nd gen antihistamines

Skippa

Anti-BS
Messages
841
Hi all,

Is it generally considered safe to take a 1st gen antihistamine and 2nd gen antihistamine at the same time?

I already take a 2nd gen daily, was going to add a 1st for a couple of weeks because reasons.

Will they interact in a dangerous way? (Eg is there such thing as too much antihistamine?)

Thanks for any insights :)
 

GreyOwl

Dx: strong belief system, avoidance, hypervigilant
Messages
266
A 1st gen antihistamine will cross the BBB. It causes my daughter to crash. I think on other threads I've read you've had issues with SSRIs?

I've been told that an increased dose of cetirizine is safe.
 

Skippa

Anti-BS
Messages
841
Hiya, thanks for the response!

Yes, I have problems with SSRIs. What does that mean in this case?
 

GreyOwl

Dx: strong belief system, avoidance, hypervigilant
Messages
266
I'm not a pharmacologist (LOL) but if you have trouble with drugs that alter serotonin chemistry, then 1st gen antihistamines might play with that same balance:
http://www.ncbi.nlm.nih.gov/pubmed/18363822
(This is the only reference I can find on that, other than personal experience as a carer).

Have you tried a 1st gen antihistamine before?
 

justy

Donate Advocate Demonstrate
Messages
5,524
Location
U.K
I think SOME 1st and 2nd gens can be taken together but not all. Best to ask a doctor I think. Most 1st gens are strongly anticholergenic and Diphenhydramine can block the reuptake of serotonin.
 

Skippa

Anti-BS
Messages
841
Thanks folks, I won't take any chances then :)

Ps, yes I've taken 1st gen before, they tend to make me groggy/drowsy.