More on H2 blockers (was: Dr. Sy - why cimetidine?)

July 21, 2002

To add an internists/emergency physicians' perspective (not known

facts -- please take the below in the casual spirit it is being

presented, not as medical advice) on H2 blockers to Dr.Sy's

thoughtful anti-flush regimen:

H2 blockers block histamine receptors located primarily in the

stomach, but also located in vessels. These drugs are often

prescribed nightly for chronic hyperacidity because that's when acid

release takes place unopposed, in an empty stomach.

However, I don't think that's relevent for rosaceans; I wouldn't

think flushing is a physiologic problem during sleep. For flushing, I

would intuitively favor use of an H2 blocker such as Zantac first

thing in the morning (realizing it takes about an hour for Zantac to

fully enter the bloodstream), with a repeat dose 12 hours later only

if evening/nighttime control is also needed. (In normal stomachs,

it's probably not a great idea to inhibit acid release around-the-

clock indefinitely.)

Be sure to review Zantac's side effects and drug interactions -- they

are much fewer than Tagamet (no gynecomastia, guys! <g>), but not non-

existent.

Only H2 blockers impact on histamine-induced flushing. Those on

proton pump inhibitors such as Propulsid and Nexium will have

decreased stomach acidity, but they will have no decreased flushing

since those medications offer no histamine receptor blockade.

As Dr. Sy suggests, consider also an H1 blocker (antihistamine).

Avoid those that cause fatigue; though safe they tend to provide an

unnatural sleep so avoid taking them chronically at night. The second

generation antihistamines are weaker but tend not to cause drowsiness

at prescribed doses (unless taken with alcohol). For example, Allegra

is a twice-daily that can be taken with Zantac in the morning,

repeated taken 12 hours later if needed at night.

Taking both an H1 and an H2 blocker together may help those who don't

respond to either. Even so, there may not be total cessation of

flushing -- but an improvement is an improvement. <g>

A dated but seemingly accurate online reference on antihistamines at

http://www.alphanutrition.com/allergy/antihistamines.htm

describes the various generic and trade name drugs.

Dr. Sy also suggests treating the release of other peptides that can

induce vasodilation such as prostaglandins, complement and

bradykinins. Note that aspirin or NSAIDs can actually cause flushing

soon after ingestion in some aspirin-sensitive individuals. For those

that can tolerate aspirin, I would think that once daily dosing of

the lowest amount taken anytime should be more than sufficient.

For those with high blood pressure, note that a number of medications

cause flushing as a side effect. Two medications that are effective

in both lowering blood pressure and decreasing facial flushing are

beta-blockers such as propanolol (also used for social anxiety), and

clonidine. As an aside: there was a recent thread discussing how to

discontinue clonidine. Since rebound symptoms can be dangerous, I

recommend that be done only under a doctor's supervision. Both drugs

have a number of side effects that should be reviewed with a

physician before use; for example, those with asthma should not take

propanolol since it can induce bronchospasm. Both are generally safe,

but their side effect provide needs to be reviewed. There are good

reasons both are only available by prescription only.

There are several reasons why those looking for medical management of

flushing need to be under a general physician's care. Not only is it

critical to eliminate other causes of flushing, but despite some of

these drugs being available OTC for other conditions (acid stomach,

allergies, pain control, etc), taking them for flushing is different,

and really does require a physician's monitoring. I think that

whatever drug(s) work for flushing should be used, I don't understand

the distinction here between prescription or non-prescription. Also,

I wouldn't intuitively recommend starting out by taking them all at

one time. A physician can help individualize a medical management of

flushing. Finally, there are other drugs available to discuss with

your doctor, the above is not exhaustive by any means. All rosaceans

deserve not only good skin and cardiovascular care but to give

attention to the psychological effects of flushing so many here

describe.

I'd appreciate not receiving private email with questions on symptoms

or make a cyberdiagnosis but maybe this can help everyone: a few

months ago I posted several messages about immunologic disorders;

it's totally appropriate for a general physician to perform the

necessary (non-routine) blood work and/or make referral to a

rheumatologist for a consellation of non-specific symptoms, to rule

out any treatable or progressive condition that would benefit from

intervention (although usually none is found).

Also, a few days ago I wrote about the distinction between facial

redness from inflammation, and facial redness from flushing; it is

confusing, but I don't see why both can't coexist, where local

irritative redness at rest appears to develop into a whole face

affair when superimposed with flushing from exercise.

Conversely, temporarily losing one's red face during exercise (unless

related to specific medication) may represent a cardiovascular

problem requiring further investigation -- at a minimum a good

history and exam, with possibly an ultrasound and/or cardiovascular

stress test. Let your doctor know what happens to your pulse when you

exercise.

Marjorie

Marjorie Lazoff, MD

> From: " mschmidt "

> > Maybe Dr. Sy will see this and explain to the group> her choice of

> cimetidine (tagemet) - since this> question has come up before: >

why Dr Sy

> chooses > > cimetidine to avoid > > flushing and not any other h2

>blocker

>

> Hi,

> Thanks for giving me this opportunity to clarify my anti-flushing

regimen.

> As I recall, the gist of my regimen was to keep it over-the-counter.

> Therefore, the products recommended were examples of OTCs. Other H2

blockers

> such as zantac or pepcid should work. As Marjorie pointed out,

zantac may be

> better since it is a BID (twice a day) dose as opposed to QID (4

times a

> day).for cimetidine. Although suggesting a QD (once daily) dose may

sound

> like taking a placebo, I have seen patients respond to this minimum

dosage.

> In fact, H2 blockers are given as QHS (once nightly) dose for

maintenance

> once the acute condition is under control. Therefore, if once a day

dosage

> works for you, keep it that way. As for drug interaction and side

effects,

> most medications have both - you just have to read the drug inserts

and be

> aware of interaction with the medications you may be taking. Or,

check with

> your doctor.

>

> Another clarification - Other H1 blockers will work as well. I

suggested

> chlortrimeton for the same OTC reason. As a matter of fact, H1

blockers that

> do not cause drowsiness and are long-lasting, such as zyrtec and

allegra,

> may be more practical. However, you need a prescription for both.

>

> Re a substitute for aspirin, other NSAIDs which are prostaglandin

inhbitors

> such as ibuprofen and indomethacin are alternatives if one is not

able to

> take aspirin.

> However, please be aware that before you take this regimen, you

should be

> under the care of a physician. Check the feasibility of these

medications

> with your primary care doctor who knows your medical situation and

current

> medications better than I.

>

> Sy MD

> Sy Skin Care

> http://www.lindasy.com

> Voice:Toll-free 877-sy (546-3279)

> Outside U.S.:

> FAX:

>

July 21, 2002