B. Agents that act in the central nervous system
C. Agents that act on adrenergic neurons
Sympathoplegic drugs are used for all degrees of hypertension be-
cause of their wide range of efficacy. Low doses of propranolol and
other beta-blockers are very widely used. Reserpine was formerly used,
but is now rarely prescribed to new patients because of adverse effects.
Methyldopa, clonidine, prazosin, guanabenz, and guanfacine are drugs of
intermediate efficacy and toxicity. Guanethidine and guanadrel are high-
ly efficacious and also have a high incidence and severity of toxicity.
Trimethaphan and mecamylamine are ganglion blocking agents with very
high efficacy. However, trimethaphan is used only in the acute treat-
ment of malignant hypertension and for the production of hypotension in
surgery; mecamylamine is obsolete and should be avoided.
A. Beta adrenoceptor blocking drugs
B. Centrally-acting sympathoplegic agents
C. Drugs acting on the sympathetic postganglionic nerve terminal
D. Alpha Receptor Blocking Drugs