[wholinator2]

Jus fyi but the "non drowsy" antihistamines are fundamentally different or anything, they're just the same type of drowsy antihistamine but with the dose lowered so it barely works unless you take more than one, thereby making it drowsy again

[tysam_and]

This is incorrect enough as to be dangerous (IMPE, I am not a doctor). They are non-drowsy because they do not cross the blood brain barrier effectively as I understand. Second and third generation antihistamines are fantastic.

[nick__m]

While I agree with your comment, for some peoples non-drowsy antihistamines are a myth.

I must be overly sensitive or have a deficient BBB because 10 mg loratadine transform me into a lethargic zombie for about 48 hours while providing minimal relief. A double dose of vyvaanse and a few coffees are not enough to bring me out of that state.

[borski]

That is definitely not the common reaction. Something is unique to you, in that regard.

[PaulHoule]

I had brain zaps with Zyrtec (Cetirizine) that took me a while to recognize for what they were because I thought they were related to other meds I was taking. I find Allegra (Fexofenadine) agrees with me a lot better. Personally I hate Claritin (Loratadine) as it definitely makes me depressed.

Experience with those others makes me wary of using Allegra except when my allergy symptoms are really bad.

BTW: Benadryl (Diphenhydramine), which has the same ingredient in the same dose marketed as a sleep aid, is really good for Poison Ivy because of its ability to penetrate into tissues really well. 30 years ago you would get a prescription for a round of steroid pills that will have you feeling pretty messed up for a week if you got Poison Ivy but today you are likely to be told to go to the pharmacy and treat yourself with OTC pills. Poison Ivy is bad enough that most people will take the drowsiness.

[tysam_and]

Nope! Plenty of people get drowsy effects from non-drowsy antihistamines. It is different for everyone (though, again, I am not a doctor!)

[gsquaredxc]

This isn't true. H1 antagonists, which is the group of drugs commonly referred to as antihistamines, contains two subgroups of pharmaceuticals. There are the first generation antihistamines, which are generally more popular and earn the reputation of making you drowsy, and the second generation antihistamines. The second generation antihistamines are significantly more selective for the H1 receptors you want to block versus the ones in your brain. Doxylamine is a first generation drug marketed under the brand name Unisom for insomnia, whereas a common second generation antihistamine loratadine commonly includes the phrase "non-drowsy" on the box. It still increases sedation, but at a substantially lower rate than the first generation drugs.