Jyothsna, you have not mentioned your age and weight to let me correlate your hypertension with causative factors - Primary or Secondary hypertension. If you have been on medication for hypertension, I would not suggest to practice agnisara kriya, to be on safer side. You should discuss this issue of hypertension with your Guru, if diet (even in collaboration with qualified nutritionist), meditation (destressing tool) and shatkarma (detoxification/elemination practices) can help you to deal with hypertension.