Hi, I understand your concern. Lisinopril is an ACE inhibitor used to treat high blood pressure (bp). Sometimes, it can be so effective to cause normal to low bp. Unfortunately, your body got used with high bp, so, these reduced levels might be associated with symptoms like dizziness. However, other causes should be ruled out including: vestibular disorders, spondyloarthrosis of the neck. So, the very first thing I suggest is to monitor your bp, record the results in order to pass them to your physician for reference. If everything is ok, then, further ENT examination and Xray of neck area recommended to rule out the other diagnosis for proper management. Hope this helps.