Patients should consult their physician before taking any other over-the-counter or prescription medication .This includes herbal remedies or nutritional supplements, which may contain stimulants. Of particular concern to patients taking antiarrhythmics are:

• Other antiarrhythmics. Taking these medications in combination with each other may worsen heart rhythm problems.
  
  
• Anticoagulants. These medications prevent the formation of blood clots, and some antiarrhythmics may intensify their effects and cause bleeding problems.
  
  
• Antihypertensives. Medications used to treat high blood pressure (hypertension). These include ACE inhibitors, alpha blockers, calcium channel blockers, angiotensin receptor blockers and some diuretics.
  
  
• Antimyasthenics. These medications are used to treat a rare muscular disorder called myasthenia gravis, and some antiarrhythmics can block their effects.
  
  
• Antidyskinetics. These medications are used to treat a rare disorder called Tourette syndrome, and some antiarrhythmics can block their effects.
  
  
• Antidepressants. These medications are used to treat clinical depression, and some antiarrhythmics can block their effects.
  
  
• Insulin. Certain antiarrhythmics may affect the insulin used to treat diabetes, or affect other oral medications for diabetes.
  
  
• Urinary alkalizers. These medications make urine less acidic and may cause a buildup of some antiarrhythmics in the body.

There are other conditions that may prevent an individual from using certain antiarrhythmics, including:

• Asthma or other lung problems (e.g., chronic bronchitis, emphysema)
• Atrial fibrillation
• Thyroid problems
• Liver disease
• Kidney disease
• Pregnancy or breastfeeding
• Lupus

Individuals with any of these conditions should discuss the use of antiarrhythmics with their physician.