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Negative chronotropic effects of nizatidine
Gut
|June 1, 1991
Summary
Nizatidine, unlike famotidine, significantly reduced resting heart rate in healthy volunteers. Both drugs, however, decreased cardiac output, warranting caution in elderly patients or those on beta blockers.
Area of Science:
- Pharmacology
- Cardiovascular Physiology
Background:
- H2 receptor antagonists are widely used for acid-related disorders.
- Potential cardiovascular effects of these drugs require thorough investigation.
Purpose of the Study:
- To compare the cardiovascular effects of nizatidine and famotidine.
- To evaluate the impact of nizatidine on heart rate during rest and exercise, and in combination with atenolol.
Main Methods:
- Randomized, placebo-controlled, double-blind study in 12 healthy volunteers.
- Administration of nizatidine (300 mg), famotidine (40 mg), and placebo once daily for one week.
- Cardiovascular parameters assessed included heart rate, pre-ejection period, left ventricular ejection time, and cardiac output.
Main Results:
- Nizatidine significantly reduced resting heart rate compared to placebo; famotidine did not.
- Both drugs increased pre-ejection period and decreased cardiac output.
- Nizatidine slightly inhibited exercise tachycardia and further reduced heart rate when co-administered with atenolol.
Conclusions:
- Nizatidine exhibits negative chronotropic effects, distinct from famotidine.
- Caution is advised when using nizatidine in elderly patients, those with heart failure, or those concurrently taking beta blockers.
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