I'm hypertensive. i was told that it's best to take medicine in the evening and not daytime. is this true?

Hypertension: The time of the day to take your hypertensive medication depends primarily on the side effects related to the medication. If you experience little or no side effedts such as dizzyness or sluggishness during the day than the mornings are suitable. If these side effects are a problem then taking the medication before bedtime avoids any of these side effects.

Medication timing: The timing of medications for blood pressure control has not been well studied. Recently a publication suggested nightime dosing to more mimic the blood pressure patterns of people with normal blood pressure. In my experience the timing of the medication is less important compared to the consistency of taking the medication. Most people take diuretics in the morning though to avoid nighttime urine.