What's the average blood pressure reduction ability of angiotensin receptor blockers when used as monotherapy? whats the maximum reduction? i'm trying to understand what to expect from these drugs?

The effectiveness varies a lot among individuals, somewhat depending on the formulary, dosage and terrain. Maximal reduction of systolic pressure is much less than 40 mmHg and the average reduction is around 20 mmHg by my experience. So for a person with a systolic pressure of 180, monotherapy with ARB is less likely strong enough for achieving an optimal systolic pressure of less than 130-140.