Can extreme anxiety prevent high bp meds from working properly? i take losartan & propranolol & my bp is still elevated.

No but: Anxiety will not nullify your meds but BP normally fluctuates in response to activity and stress, so if you're anxious when you check your BP, it may be falsely elevated. Check your BP 3 times whenever you measure it and measure it often - by doing this, you'll become indifferent to having it checked and less likely to react so vigorously. Always measure at complete rest. Average your readings.