I m having high blood pressure . arround 160/90.. i am feeling lightheadness all time .my age is 24 . its feel really bad :-(?

See qualified MD: You need to see a qualified md right away - preferably western trained or at a western hospital in india. Your blood pressure is high for two reasons - the number itself but also you are having symptoms of light-headedness. This can be dangerous. For your part, exercise daily (does not have to be vigorous), lose weight if overweight, stop smoking, reduce fat/meat/dairy intake, ; reduce salt use.

Get worked up: You need a full evaluation including a check for renal artery stenosis, aldosteronoma, pheochromocytoma and some others. Until this is completed, there's no addressing why you are light-headed. If your personal physician will not pursue this aggressively, then get a consultation. Best wishes.

Unrelated: It's distinctly abnormal for a 24 year old to have high blood pressure which suggests something else is going on (renal disease?) . Your blood pressure would cause no symptoms at all - it definitely doesn't account for your dizziness. A rapid reduction in BP could make you dizzy - that would depend on the dose and length of time you've been taking your medication. Sorry you're feeling bad.