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Aspirin blocks nicotinic acid-induced flushing
Clinical Pharmacology and Therapeutics
|April 1, 1982
Summary
Aspirin reduces the intensity of nicotinic acid-induced skin flushing in a dose-dependent manner. This suggests that prostaglandins play a role in the flushing reaction, which is a variable, nonquantal response.
Area of Science:
- Pharmacology
- Human Physiology
Background:
- Nicotinic acid (niacin) is known to cause skin flushing.
- The exact mechanism of this flushing response is not fully understood.
- Prostaglandins are suspected mediators of this side effect.
Purpose of the Study:
- To investigate the effect of aspirin on nicotinic acid-induced flushing.
- To quantitatively assess the intensity of flushing using the malar thermal circulation index (MTCI).
- To explore the role of prostaglandins in this physiological response.
Main Methods:
- 29 healthy subjects participated in the study.
- Subjects received varying doses of nicotinic acid after pretreatment with either placebo or 975 mg of oral aspirin.
- Flushing intensity was measured by the change in the malar thermal circulation index (delta MTCI).
Main Results:
- Aspirin pretreatment significantly reduced the intensity of flushing (delta MTCI) at higher doses of nicotinic acid.
- At lower nicotinic acid doses, both aspirin and placebo groups showed minimal flushing.
- The delta MTCI method characterized flushing as a variable, nonquantal, dose-response reaction.
Conclusions:
- Aspirin attenuates nicotinic acid-induced flushing, particularly at higher nicotinic acid doses.
- These findings support the hypothesis that prostaglandins mediate the flushing response to nicotinic acid.
- Nicotinic acid flushing is a quantifiable, dose-dependent physiological reaction.
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