You should not use sotalol if you have asthma, low potassium, or a serious heart condition such as severe heart failure, long QT syndrome, slow heartbeats that have caused you to faint, "sick sinus syndrome" or "AV block" (unless you have a pacemaker).
You will receive your first few doses of sotalol in a hospital setting where your heart can be monitored in case the medicine causes serious side effects.
Before taking this medicine
You should not use sotalol if you are allergic to it, or if you have:
a serious heart condition such as "sick sinus syndrome" or "AV block" (unless you have a pacemaker);
long QT syndrome (in you or a family member);
severe heart failure;
slow heartbeats that have caused you to faint;
asthma or other breathing disorder;
very low levels of potassium in your blood; or
(if you take sotalol for atrial fibrillation or atrial flutter) severe kidney disease;
Do not give  sotalol to a child without medical advice.
Tell your doctor if you have ever had:
kidney disease (or if you are on dialysis);
an electrolyte imbalance (such as low levels of potassium or magnesium in your blood);
congestive heart failure;
coronary artery disease (hardened arteries);
breathing problems such as bronchitis or emphysema;
a thyroid disorder;
diabetes (using sotalol can make it harder for you to tell when you have low blood sugar);
a severe allergic reaction.
Tell your doctor if you are pregnant.
You should not breastfeed while using sotalol.
