Hi, thanks for writing. patients who are on antihypertensives for longer period most of them at some moment encounter low blood pressure (Medication related) either due to overdose of drugs or meteo (Climate) or sometimes faulty apparatus. I would recommend you to continue keeping a record of your readings ( regularly for a week atleast ) and avoid apparatus especially one which measures on the wrist. Readings should be taken from both arms and take the average reading as blood pressure at that moment. If blood pressure continues to drop please reduce dose of lisinopril upto 5mg ( can be reduced to 2.5 mg also) once daily initially, but do not cut the medicine completely. As far as pulse is considered it seems to be within normal range, lisinopril doesn t have direct effect on heart rate though. Please refer back to us or your physician for further evaluation if required. I hope that answers your question. Dr.Uppal