- Ventricular tachycardias
- Asthma
- Diabetes
- Heart block
- Hyperthyroidism
- Kidney disease
- Sinus bradycardia
- Uncontrolled congestive heart failure
- Aloe
- Anesthesia
- Calcium channel blockers
- Furosemide
- Insulin
- Labored breathing
- Lethargy or depression
- Loss of appetite