Benadryl?

[ZZZzzz]

I love it when due to allergies I need to take Benadryl !

It makes me delightfully sleepy. I can't take it unless I need to or it dries me out.

I don't get to take it that often because my allergy shots do a good job of controlling my sniffles.

-Bev

[StillAnotherGuest]

The biggest problem with diphenhydramine is its half-life, which is basically who the heck knows. Could be 9-12 hours (as noted, the case of next-morning grog), more if your liver is on the fritz, are elderly, or are taking more than one like-drug (don't Google antihistamine, use anticholinergic instead).

Cognitive and Other Adverse Effects of Diphenhydramine Use in Hospitalized Older Patients

Drugs with anticholinergic properties and cognitive performance in the elderly: results from the PAQUID Study

Maybe It Do and Maybe It Don't

Anticholinergic Agents
This class includes drugs with known anticholinergic properties such as the first-generation, sedating antihistamines (eg, diphenhydramine, hydroxyzine, chlorpheniramine, meclizine), antispasmodics (eg, belladonna, diphenoxylate, clinidium, dicyclomine, hyoscyamine), oxybutynin, trazodone, ipratropium bromide, tricyclic antidepressants (which are discussed separately under antidepressants), phenothiazines (eg, thioridazine, prochlorperazine, promethazine, chlorpromazine, fluphenazine), muscle relaxants (cyclobenzaprine, orphenadrine), mydriatics (atropine, homatropine, tropicamide), diphenoxylate/atropine, antiparkinsonian agents (eg, benztropine, trihexyphenidyl), and antiarrhythmics (eg, disopyramide, quinidine, procainamide). Further, other drugs which may have possible anticholinergic effects include codeine, colchicine, warfarin, digoxin, furosemide, haloperidol, isosorbide dinitrate, meperidine, nifedipine, cimetidine, ranitidine, prednisolone, quinidine, and theophylline.[10,35-37] Many drug classes starting with the prefix "anti" have anticholinergic properties (eg, antihistamines, antidepressants, antipsychotics, antispasmodics, antiparkinsonian drugs, and some antihypertensives) and may help alert the practitioner to drugs that may be a source of confusion in their patients.[38]

Anticholinergic agents have been causally linked to the development of memory impairment in healthy subjects. Memory impairment may be associated with basal forebrain cholinergic pathways, whereas changes in consciousness seen in delirium may be attributable to alterations in pontine cholinergic pathways projecting into the frontal cortex and brain stem. Acetylcholine is also involved with attention, the sleep-wake cycle, and other aspects of cognitive functioning.[8,13]

In a study that was published in 1983, approximately 60% of nursing home residents and 23% of ambulatory patients were receiving drugs with anticholinergic properties. In some cases, patients may have received 3 or more anticholinergic medications concurrently.[39]

Tune and others[36] examined the anticholinergic effects of drugs commonly prescribed for the elderly as a potential means for assessing risk of delirium (Table 4). Using a standard concentration of 10-8 M of 25 compounds and an anticholinergic radioreceptor assay, they assessed these substances against an internal standard of atropine. Atropine equivalents represented in nanograms per milliliter of equivalent amounts of atropine were compared to the test drug. Of the 25 drugs tested, 14 produced detectable anticholinergic effects with 10 of these 14 medications, resulting in anticholinergic levels that have been associated with significant deficits in memory and attention in normal elderly.

Medications that were not associated with anticholinergic effects in this study included hydrochlorothiazide, propranolol, salicylic acid, nitroglycerin, insulin, methyldopa, ibuprofen, diltiazem, atenolol, metoprolol, and timolol.[36]

In an earlier paper, Tune and colleagues[40] had found that postoperative cardiac surgery patients who had experienced delirium had high serum levels of anticholinergic drugs and that impairment in cortical function was related to this elevated level. This group later examined the cumulative anticholinergic effects of drug regimens among surgical intensive care unit patients.[41] They have since expanded their work to examine the anticholinergic effects of 48 commonly prescribed medications.[42]

Flacker and colleagues[35] analyzed the association of serum anticholinergic activity with delirium in medical patients aged 75 or older. Delirium was associated with a higher serum anticholinergic activity quintile. The number of symptoms of delirium were also associated with higher serum anticholinergic activity. Mach and colleagues[43] demonstrated the resolution of delirium in an elderly population upon discontinuation of medications, which resulted in a reduction of serum anticholinergic levels. Only 5 of 17 medications discontinued were known to have in vitro anticholinergic activity. Even topically administered anticholinergic ophthalmic preparations have been associated with the development of delirium.[44,45] Other investigators have reported the presence of high serum anticholinergic levels among patients who have not received a drug that blocks acetylcholine, which raises the possibility of an endogenous source of anticholinergic activity that may possibly increase during times of stress.[35,46] Among elderly nursing home residents, serum anticholinergic activity seems to increase during illness and declines upon recovery, regardless of medication changes.[47]

In the presence of central anticholinergic toxicity, the use of physostigmine (a 1- to 2-mg test dose) may rapidly improve mental status. However, this drug has many severe side effects, including increased secretions, bronchospasm, vomiting, aspiration, and bradycardia, so its routine use cannot be advocated in the elderly.[10] The value of acetylcholinesterase inhibitors such as donepezil in this setting is unclear. Often, removing the causative agent and offering supportive care may be sufficient.

In summary, the likelihood of developing delirium following ingestion of an anticholinergic is unpredictable and may depend on other concomitant medications that exert anticholinergic effects, baseline cognitive status, pharmacokinetic or pharmacodynamic effects, specific agent used, and the total anticholinergic burden.[18]

It should also be stated that despite all of this evidence, the association between anticholinergic drugs and the development of delirium is not universally accepted. Francis and coworkers [4] and Schor and colleagues[48] failed to demonstrate causality between the use of these agents and the development of delirium in elderly medical inpatient populations. Yet others have felt that the lack of association between delirium and anticholinergic drugs in epidemiologic studies is one of misclassification of drug effects rather than the inability of the anticholinergic effects of drugs not to produce delirium.[14]

How does one self-assess long-term drug use? I mean, you don't just wake-up one morning and say. "Hmmm, nice day. I think I have cognitive impairment."

Is 25 mg of Benadryl every night (over 4 pounds per year) gonna keep your brain razor-sharp?

I guess an alternative question to that would be:

Is 6-8 hours of drug-induced sleep better than 2-4 hours hours of fragmented sleep?

You're probably better off doing shotgun Essential Oils and running the risk of Lipoid Pneumonia.

Only kidding!!

Actually, I think the study there should be for lung diffusional impairment over long-term use.

In closing, the relationship of long-term anticholinergics and cognitive impairment is...

is...

Hey! How did I get here?

SAG

[Guest]

Wow.

Well, since I WAS diagnosed with Fragmented Sleep, and without Benadryl, I sleep less and less and less on the hose, I find it necessary.

This morning I woke up at 5 am. I predict by Friday I'll be back to 3 am wide awake. And I went to bed after 12:30 pm. It doesn't really seem to matter when I go to sleep - when I start the cycle of waking up earlier and earlier, it just HAPPENS, no matter how tired I am, no matter how early or late I go to bed.

It used to happen OCCASIONALLY pre-therapy, but now I've noticed there's a definite cycle. I'll do this for awhile, until it gets to about 3 am, then I'll take Benadryl for a few weeks, get back to a "regular" routine, then slowly it will creep back up.

Cheers,
B.

[new-to-BiPAP]

I haven't noticed too many problems with benadryl except it can dry me out and make me a bit groggy in the morning. Sometimes I take it an hour or so before I need to go to bed. If I take it for too long it does temporarily loose it's effectiveness My MIL did have a problem with it...she took it for a long time for allergy problems and now when she takes it, it does NOT make her sleepy at all. I usually start out with one a night...then when that doesn't work go to 2...then I have to stop it for a while...then start with one again...

[marielouise]

I too have taken both Benadryl and the off brands but more for skin allergies I'm apparently allergic to something that causes hypercarotosis almost every night and some times during the day that drives me bazerk. I've taken it for so long that in order to achieve any relief at all I have to take 4 or 5. I know this couldn't be good for anyone. More and more lately I just say to heck with it and tough it out without any. What is concerning is that one day I'll get a bee sting or something else & won't be able to remedy it myself with anything over the counter.

[Guest]

I've used it for years. It doesn't help me MUCH when I'm congested - but I've been taking too many antihistimines for too many years. YMMV.

I take it STRAIGHT, in generic form, as a sleep aid.

No real side effects, other than sometimes I'm groggier in the AM than usual. I can still get up and go to work, it's just that my coworkers sometimes wish I hadn't.

I'd recommend it to try to short-term congestion. I'd also experiment with VERY SMALL doses of pseudoephedrine. Unless you have HBP. And take it plenty early in the day, so you can sleep.

Cheers,
B.

[Guest]

ooops...

Didn't realize this was a recycled thread. Thought it was new. And didn't read the whole thing before I posted the previous.

Sorry!
B.