Aspirin Withdrawal May Pose Risk To Coronary Patients

Science Daily ^ | 10-30-2003

[Old Professer]

I wonder how researchers determined the 81 mg dosage.

Tylenol (acetominophen) lobby.

[Old Professer]

I've read studies that say there's no benefit above 81mg a day.

Have you read the study or the report promulgated to that effect?

[RightWhale]

two 325 tablets to take immediately

Do you chew them up and swallow dry--German style?

[Old Professer]

A standard aspirin tablet is 325 mg; a baby aspirin is 1/4 dosage=80.25mg. Doctors have long known that the indiscriminate use of aspirin (unbuffered) leads to stomach lining irritation and some bleeding so they are reluctant to recommend more than the minimum dose that has been shown to provide a benefit.

In order to reduce stomach irritation, many aspirin tablets are enteric-coated, which simply means they don't dissolve readily in the stomach and they are considered less harmful from that perspective.

An easy, though more expensive, way to get your daily protection would be to take two Alka-Seltzer tablets which are made up of acetylsalicylic acid (aspirin), citric acid and sodium bicarbonate (baking-soda) mixed as a powder and compressed into tablet form.

Since I don't find the convenience or the effervescence worth the extra cost, I simply buy the non-enteric tablets (store-brand 325mg) and baking soda and mix my own in cool water - it's terribly nasty in warm or hot water.

[Old Professer]

What kind of a scan did you have that showed zero build-up in the arteries?

[Old Professer]

One of the studies indicated that the carviovascular therapeutic effect of aspirin (ASA)is reached at 1/20 of a single 325mg aspirin tablet.

Would you be so kind as to point me to a site where I could read that study?

[blam]

Good catch. I read the report of the study.

[Old Professer]

The magnitude of the apparent effect is such that the entire benefit derived from statin therapy can be reversed almost immediately.

It would seem obvious that for any anti-coagulent benefit to accrue due to the ingestion of aspirin that the amount of aspirin necessary to provide this benefit would have to be maintained in the bloodstream at all times; amounts in excess of this level, but below stress-effect level on sensitive tissue should be the maximum recommended dosage for all at-risk patients, IMO.

[Old Professer]

I also carry a small tin with two 325 tablets to take immediately on onset of any significant symptoms..... I don't leave home with out it.

You might want to carry Goody's Headache Powder in foil packets, as it could be placed directly beneath the tongue just as nitroglycerin is.

[Old Professer]

Coagulent should be coagulant, sorry.

[NautiNurse]

Of course, I will never be able to find that silly study--primarily because it has been refuted. However, there are several sources indicating 30mg (<1/10) of an adult 325mg tablet for prevention. Can be located via Google search. Otherwise, here is a reasonable summary of literature:

Anticoagulation and Antiplatelet Therapy: Aspirin, GlycoproteinIIb/IIIa Inhibitors, and ADP Platelet Receptor Antagonists

Susan B. Promes, MD
Gideon Bosker, MD, FACEP

Dosing. Aspirin dosing is controversial, with various studies or editorials confirming, recommending, or reporting that aspirin doses from 30 to 1400 mg/d are effective for specific clinical conditions.⁴ Most studies and consensus panels, however, recommend aspirin dosages between 81 and 325 mg/d.⁵ (See Table 3.)

Table 3. Minimum Recommended Dose of Aspirin for Common Indications
Thrombotic Disorder	Minimum Effective Daily Dose
Stable Angina	81 mg
Unstable Angina	81 mg
Acute Myocardial Infarction	160-325 mg
Transient Ischemic Attack	81 mg
Atrial Fibrillation (warfarin contraindicated or young/lone atrial fibrillation)	325 mg
Atrial Fibrillation (in addition to warfarin in case of failure)	325 mg
Secondary Prevention of MI	81-162 mg

There is also conflicting information with respect to the relationship between aspirin dose and side effects, although lower doses appear to be associated with a lower risk of hemorrhagic complications. Moreover, women seem to be at higher risk for aspirin-related complications. When the the objective is secondary prevention of MI, the goal is to use the lowest dose of aspirin required to inhibit thromboxane, yet spare prostacyclin production. Although the mechanism of gastrointestinal side-effects is not well understood, these complications are thought to be related, at least in part, to inhibition of prostacyclin, which is thought to occur at higher aspirin doses.⁶ There have been intriguing reports of “booster” dosing of aspirin, in which patients taking 81 mg/d of aspirin for long-term prevention, take one 325 mg aspirin tablet every 15 days, in order to enhance cardiprotection. Although one study suggests enhanced outcomes with this dosing pattern, additional trials are required to establish the efficacy of this approach.

4. Hart RG, Harrison JG. Aspirin Wars: The optimal dose of aspirin to prevent stroke. Stroke 1996;4:585-587.

5. Hirsch J, Dalen JE, Fuster V, et al. Aspirin and other platelet active drugs: The relationship among dose, effectiveness, and side effects. Chest 1995;108:247S-257S.

[bert]

So far I just carry them. The Bayer research says to chew them up finely.

Goody's is a good idea, but packaging might be a problem. The small metal tin I carry contains a foam insert drilled to accept the tablets. It keeps them uncontaminated and dry.

I might need to redesign the whole package to accomodate the powder. I'll think on it.

[tubebender]

I was scheduled for minor surgery Tuesday but had to cancel because I forgot to stop the 1/4 grain aspirin 10 days prior. Anyone taking aspirin must be aware of potential bleeding externally and internally. I also carry a tin of aspirin and have instructed my grandson and family to be aware of it if I collapse...

[blam]

"I also carry a tin of aspirin and have instructed my grandson and family to be aware of it if I collapse..."

I've read that taking aspirin is the best first thing you can do during a heart attack.

[Kozak]

Yeah, but better hope your collapse is not due to GI bleed, or a hemorrhagic CVA. Taking an aspirin is a fine idea if you are awake and having chest pain, sticking one in the mouth of someone unconcious is not a good idea....

[Old Professer]

Nothing in that table covers primary prevention of MI.

[NautiNurse]

A simple Google search will turn up loads of info for your research pleasure.

[jwalsh07]

I've been taking 325mg enteric for about a decade. Has some unanticipated benefits.

I'm always the first done at the blood bank.

[bmwcyle]

Click Here

[bmwcyle]

Only the smart ones look on the lower shelves.