How long it takes for high blood pressure to cause atherosclerosis months years or decades can a person with only month of high bp be at risk of developing it even if bp is normal after one month?

Untreated high blood pressure is not only a risk factor for atherosclerosis, but also for heart disease, stroke, and dementia. Any of these are bad outcomes. If your blood pressure is normal after one month on antihypertensives, this is the expected result and your medication should be continued. Do not change your dosing. Work closely with your doctor.