IT IS CONVERTED TO ALPHAMETHYL NOREPINEPHRINE WHICH STIMULATES CENTRAL ALPHA ADRENERGIC RECEPTORS IN BRAIN THEREBY DECREASING SYMPATHETIC OUTFLOW. PRIMARILY DECREASES PERIPHERAL RESISTANCE WITH LITTLE EFFECT ON CARDIAC OUTPUT. IT MAY ALSO ACT AS A FALSE NEUROTRANSMITTER, AND HAVE SOME NHIBITORY ACTION ON PLASMA RENIN ACTIVITY. METHYLDOPA REDUCES THE TISSUE CONCENTRATION OF DOPAMINE, NORADRENALINE, ADRENALINE & SEROTONIN.