Abstract

Patients with dangerously low blood pressure are often treated with drugs whose major effect is to increase the peripheral resistance, such as angiotensin (Hypertensin - Ciba), noradrenaline, methoxamine (Vasylox - BW), metaraminol (Aramine - MSD) or phenylephrine. Though these indisputably raise the blood pressure, they generally do so at the expense of a fall in cardiac output, and in man the prognosis is not necessarily improved. Indeed good theoretical reasons and abundant experimental evidence in animals (including primates) suggest that the drugs are seldom beneficial and may sometimes do harm.¹