what are side effects of low heart rate.

Hello Anon

Thank you for writing.

Bradycardia is an abnormally slow heart rate. In adults, it is defined as a heart rate of less than 60 beats per minute. Different types of bradycardia include (collectively referred to as “bradyarrhythmias”) :

Sinus bradycardia—an unusually slow heartbeat due to heart disease, a reaction to medication, or normal causes (such as excellent fitness or deep relaxation)
Sick sinus syndrome—an unusually slow heartbeat due to a malfunction of the heart’s natural pacemaker (sinoatrial node)
Heart block (atrioventricular block or AV block)—an unusually slow heartbeat due to a slowing or blocking of electrical impulses in the heart’s conduction system

Some types of bradycardia produce no symptoms. Others may cause noticeable symptoms, such as:

Fainting or loss of consciousness (“syncope”)
Dizziness, sensation of light-headedness
Weakness
Mild fatigue
Sensation of your heart fluttering (palpitations)
Shortness of breath
Chest pain
Low blood pressure (hypotension)
Serious forms of bradycardia, such as complete heart block, are medical emergencies. They can lead to loss of consciousness or sudden cardiac arrest .

Please consult further with your doctor.
Best,
Susan