Good afternoon Dear As per your words you are suffering from sensitivity due to cold water,  Most common  reason for increase  in sensitivity is Hard Brushing or improper brushing technique. Regarding Sensitivity paste thr are certain norms to apply that to have better results. Visit a Periodontist (Gum Specialist) for better and proper remedy. Regards Dr. Aman Bhatia Chandigarh www.dentafix.in

Sensitive tooth is due to improper brushing techniques.....use vantej(dr reddy)toothpaste twice in a day n use oral -B soft bristles

Sensitivity can be caused by many reasons. There is no harm in using sensitivity toothpastes but if your sensitivity is due to cavities etc then they should be filled. You can continue to drink cold water