EXAMPLES  Noradrenaline, ephedrine, phenylephrine

MECHANISM OF ACTION 

• Stimulation of peripheral a-adrenoceptors within the vasculature, leading to vasoconstriction and increased systolic and diastolic blood pressure.

INDICATIONS

• Acute hypotension.
• Cardiac arrest.

CAUTIONS AND CONTRA-INDICATIONS

• Hypertension

SIDE-EFFECTS

• Hypertension.
• Headache.
• Arrhythmias.
• Bradycardia/tachycardia.

METABOLISM AND HALF-LIFE 

• Metabolised in the liver and other tissues by MAO and COMT.

MONITORING 

• Continuous cardiac monitoring in a high-dependency area is required.
• Monitoring of oxygen saturation, urine output and renal function is also necessary.

DRUG INTERACTIONS

• Severe, prolonged hypertension when given in combination with MAOIs.

IMPORTANT POINTS

• Ephedrine can be used to treat hypotension resulting from spinal/epidural anaesthesia.