Based on the information its seems you are having "PALPITATIONS" / increased heart rate
Due to "METFORMIN" basic content of CETAPIN- XR 500 MG.
1) Increase in heart rate is rare side effect but is noted by many patients and needs to be brought under the attending physician's notice.
2) It can occur in case of LOW blood sugar
, due to high dose of medication.
3) May simply occurs due to anxiety
CONSULT PHYSICIAN, and inform the occurrence of increase in heart rate.
here are two things that may need to be addressed
1) Checking the sugar level by home strips during the increase in heart rate
2) Changing dose of the drug or completely changing the drug may help reducing the heart rate.
Hope it helps.
Dr. JAY PATEL