How long does Labetol take to work?
If you are taking Labetol for high blood pressure, it may lower your BP within 1-3 hours of taking it. You may not feel any different, but this does not mean that the medicine is not working, and it is important to keep taking it. On the other hand, if you are taking it for angina, it will probably take a few days for the medicine to reduce the pain. You may still have chest pain during this time or it may get worse.