Sedating Antihistamine With Little/No Anticholinergic Effects?

  • Thread starter Thread starter 187502
  • Start date Start date
This forum made possible through the generous support of SDN members, donors, and sponsors. Thank you.
1

187502

Members don't see this ad.
I recently had a patient inquire about an antihistaminic agent w/ little or no anticholinergic effects but is still slightly sedating, wanting it to treat chronic environmental allergies as well as help promote sleep. I said as far as I knew no such animal existed, but I thought I would double check with the pharm. people to see if I might have missed one of the less well known antihistamines. All the ones I am aware of have rather unpleasent anticholinergic properties (diphenhydramine, clemastine, etc...) or aren't sedating (loratadine, cetirizine, etc...). Any insight is appreciated.
 
Last edited:
Atarax is listed on my notes as High sedative effects and Moderate Anticholinergic effects, but nothing with low anti-ach in the high sedative category.
 
I think the closest you will get is cetirizine. 2nd generation type-1 histamine antagonists do not have any effect on muscarinic receptors. Referring to cetirizine as "non-sedating" is a relative misnomer when compared to the other the other 2nd generations.

Cetirizine is the only antihistamine in the class known as the "2nd generation piperazines," and is described as having negligible anticholinergic effects with a somewhat higher incidence of drowsiness than other 2nd generations. Other 2nd generations fall into the "2nd generation piperidine" class, so there is a pharmacologic distinction between cetirizine and the rest of them (loratadine, fexofenadine, etc.).
 
Last edited:
Zyrtec is the closest, but it's certainly not enough to induce sleep. I vote with your first answer, it does not exist.
 
May I ask, is it likely that there are specific anticholinergic properties the patient is trying to avoid? Because it looks like there are tons of side effects for anticholinergic medications, but I don't know which are common, which are rare, and which are potentially serious.

For example, I see 'increased intraocular pressure' listed--- so then should someone with glaucoma avoid Benadryl? Or is it a rare enough effect that they could probably take it anyway? I'm curious about this, since without having read about those side effects I would have thought diphenhydramine was a great choice for dealing with allergies and causing drowsiness.

If someone could explain, or point me in a better direction than wikipedia (which is where I just came from), I would greatly appreciate it!
 
Levocetirizine (Xyzal). Newer, faster, longer. Problem solved.
 
parabolic said:
May I ask, is it likely that there are specific anticholinergic properties the patient is trying to avoid? Because it looks like there are tons of side effects for anticholinergic medications, but I don't know which are common, which are rare, and which are potentially serious.

For example, I see 'increased intraocular pressure' listed--- so then should someone with glaucoma avoid Benadryl? Or is it a rare enough effect that they could probably take it anyway? I'm curious about this, since without having read about those side effects I would have thought diphenhydramine was a great choice for dealing with allergies and causing drowsiness.

If someone could explain, or point me in a better direction than wikipedia (which is where I just came from), I would greatly appreciate it!
Click to expand...

The most common side effects involve blockade of the muscarinic receptors of the cholinergic side of the autonomic nervous system.

The main side effects are:

  • Drowsiness
  • Dry mouth (salivation)
  • Inability to urinate, especially in older men
  • dry eyes (lacramation)
  • palpitations (reflex tachycardia)
  • constipation, especially in the elderly
This will in laymen's terms stop all of your "ations" salivation, urination, defacation, lacramation, lactation etc..... This will dry up all of the bodies excretions controlled by muscarinic receptors.

The increase in IOP occurs only in those patients that have narrow angle glkaucoma. Only 10% of Glaucoma patients have narrow angle glaucoma. So while it is an issue it is something that should be questioned, but for 90% of glaucoma patients, anti-muscarinic agents are not an issue.
 
BMBiology said:
Levocetirizine (Xyzal). Newer, faster, longer. Problem solved.
Click to expand...

Please tell me you're joking right. This is nothing but bent Zyrtec. Pfizer waits until the patent on Zyrtec is about to expire and they release the L-isomer and act as if they discovered a cure for cancer.
 
Old Timer said:
Please tell me you're joking right. This is nothing but bent Zyrtec. Pfizer waits until the patent on Zyrtec is about to expire and they release the L-isomer and act as if they discovered a cure for cancer.
Click to expand...

Newer. Faster. Longer = Better!
 
BMBiology said:
Newer. Faster. Longer = Better!
Click to expand...

Studies demonstrate no difference in clinical efficacy between the two. ...Patients swear that they gain a ton of weight on Xyzal and that it causes more sedation.
 
being fat makes you sleepy.
 
shaolinRX said:
Patients swear that they gain a ton of weight on Xyzal and that it causes more sedation.
Click to expand...

and where are the studies? If that's true then Xyzal can also be used for patients who want to gain weight. And if it also causes sedation, then it can compete with Ambien. It is an all-in-one drug!
 
Also, if Xyzal is no better than Zyrtec, then why would DOCTORS prescribe it and why would patients pay more for it? Makes no sense. In addition, the drug has "XYZ" letters in its name, it must be good. You guys are just not up to date on the latest studies.
 
BMBiology said:
Newer. Faster. Longer = Better!
Click to expand...
Bull feathers. That's all advertising hype.

Longer: Survey says bull feathers.

  • Zyrtec dosage: once per 24 hours
  • Xyzal dosage..: once per 24 hours
  • That means it lasts just as long as the older.
Newer: Survey says True. But so what. Is newer automatically better?

Faster: Survey says. False. They both take approximately one hour to exert their effect.

Better: Survey says: False. Please provide one study that shows any of the above to be true. How can the L-isomer be more effective than the racemic mixture.

You have been seduced by the dark side of the force.
 
Old Timer said:
Bull feathers. That's all advertising hype.

Longer: Survey says bull feathers.

  • Zyrtec dosage: once per 24 hours
  • Xyzal dosage..: once per 24 hours
  • That means it lasts just as long as the older.
Newer: Survey says True. But so what. Is newer automatically better?

Faster: Survey says. False. They both take approximately one hour to exert their effect.

Better: Survey says: False. Please provide one study that shows any of the above to be true. How can the L-isomer be more effective than the racemic mixture.

You have been seduced by the dark side of the force.
Click to expand...

Somebody is too old to understand sarcasm online.
 
I am not in the state to pick up on sarcasm right now (and I think I missed some from BMBiology just a few days ago as it is), but any pharmacist who recommends levocetirizine should burn their degree, license, and apply to nursing or medical school immediately.
 
Someone find a good study about CSF concentration of peripheral antihistimines after administration...the one that crosses the at the highest concentration at a dose that causes no toxic effects wins. That's my plan, anyway....

Or just Krazy Glue an Ambien to a Claratin. That'd work, too...
 
Priapism321 said:
I am not in the state to pick up on sarcasm right now (and I think I missed some from BMBiology just a few days ago as it is), but any pharmacist who recommends levocetirizine should burn their degree, license, and apply to nursing or medical school immediately.
Click to expand...

So does it cure cancer or not?
 
Old Timer said:
The most common side effects involve blockade of the muscarinic receptors of the cholinergic side of the autonomic nervous system.

The main side effects are:

  • Drowsiness
  • Dry mouth (salivation)
  • Inability to urinate, especially in older men
  • dry eyes (lacramation)
  • palpitations (reflex tachycardia)
  • constipation, especially in the elderly
This will in laymen's terms stop all of your "ations" salivation, urination, defacation, lacramation, lactation etc..... This will dry up all of the bodies excretions controlled by muscarinic receptors.

The increase in IOP occurs only in those patients that have narrow angle glkaucoma. Only 10% of Glaucoma patients have narrow angle glaucoma. So while it is an issue it is something that should be questioned, but for 90% of glaucoma patients, anti-muscarinic agents are not an issue.
Click to expand...

That was really helpful! Thank you.
 
WVUPharm2007 said:
I don't know how it's spelled because I don't care. Brand names deserve to be unknown.
Click to expand...

DAMN RIGHT!!!! Start using the actual drug name like a real Pharmist.
 
You must log in or register to reply here.

Similar threads

R
Effects of tariffs on drug supply chain?
Replies
1
Views
834
lord999
lord999
P
  • Locked
Effect of Trump/RFK Jr on pharmacy
Replies
3
Views
2K
owlegrad
owlegrad
V
Husson pharmacy school closing/merging with UNE
Replies
4
Views
2K
clarkbar
C
aholick243
Seeking Experience with Oral Amoxicillin Challenge Test in Pediatric Patients
Replies
0
Views
1K
aholick243
aholick243
D
  • Locked
Needing Help with my School Research Project
Replies
3
Views
917
GoSpursGo
GoSpursGo
Top