no not really. i mean it's best to take all medications on a close schedule. in other words if a medication is taken "once every 24 hours" (or "daily") it's a good idea to try to take it exactly every 24 hours. but as nurses our guideline is you can administer a medication within a one-hour window on either side of the appointed time and still be considered "on schedule. " that means you could take the blood pressure pill at the 23-hour mark or the 25-hour mark and still be considered "on schedule. " but honestly take a daily pill within a four-hour window probably isn't going to cause any problems. i would try not to make a habit of it. but if that's what works for you today you should be fine. hope this helps!
is taking bp medicine at 20 hours since the last dose harmful?