If i have chronic hypertension, should i double up on my meds to help reduce chances to prevent damage during the flight?

No: No, doubling your BP meds may lower your blood pressure too much and make you dizzy or even make you faint; don't do it !

NO, : You should keep the same dosage if your blood pressure has been under controled. Taking a flight should not affect it. Double the dosage may cause your blood pressure too low that can cause dizziness or heart rate too slow or too fast.