Salbutamol should be used with caution in persons with cardiac arrhythmias, coronary insufficiency, hypertension, hyperthyroidism, convulsive disorders, and diabetes mellitus. Significant changes in blood pressure may be found in some persons after use of salbutamol. Large doses of intravenous salbutamol may aggravate the preexisting diabetes mellitus and ketoacidosis. Salbutamol may also produce significant hypokalemia in some persons, which produce adverse cardiovascular effects.
Beta-receptor blocking drugs should be avoided during salbutamol therapy because these drugs block the bronchodilator effect of salbutamol. Beta-blockers also may produce severe bronchospasm in patients with bronchial asthma. So, asthmatic patients should avoid beta-blockers. In some cases, such as prophylaxis after myocardial infarction, there are no acceptable alternatives to use of beta-blockers in patients with asthma. In this condition, more cardioselective beta-blockers should be used with caution.
Tricyclic antidepressant (TCA) drugs or Monoamine oxidase inhibitors (MOAI):
Patients receiving TCA or, MOAI or within two weeks of discontinuation of such drugs, salbutamol should be taken with extreme caution, because the action of salbutamol on vascular system may be potentiated.
Hypokalemia due to administration of loop or thiazide diuretics may be acutely worsened by salbutamol, especially when the recommended dose of salbutamol is exceeded. Therefore, caution is advised in the concomitant administration of salbutamol and nonpotassium-sparing diuretics.
Labor and delivery:
Salbutamol may interfere the uterine contractility. Therefore, use of salbutamol during labor for relief of bronchospasm should be restricted to those women in whom the benefits clearly outweigh the risk.