Tailored to specific cause of<unk> :
Fluids for dehydration
Blood for hemorrhage
Anticoagulation/thrombolytics for PE
Antibiotics and fluids for sepsis
Benzodiazepines for alcohol withdrawal
Supportive care for intoxication
If no cause identified, treat with caution
Beta blockers or other antiarrhythmics are not appropriate for unexplained<unk>  as patient may require elevated heart rate to maintain appropriate cardiac output depending on underlying cause
May consider discharge with<unk> rict return precautions if no clear cause identified and no serious pathology suspected after careful work-up
Ensure close follow-up and<unk> rict return precautions
Fluids for dehydration
Blood for hemorrhage
Anticoagulation/thrombolytics for PE
Antibiotics and fluids for sepsis
Benzodiazepines for alcohol withdrawal
Supportive care for intoxication
Beta blockers or other antiarrhythmics are not appropriate for unexplained<unk>  as patient may require elevated heart rate to maintain appropriate cardiac output depending on underlying cause
May consider discharge with<unk> rict return precautions if no clear cause identified and no serious pathology suspected after careful work-up
Ensure close follow-up and<unk> rict return precautions
Ensure close follow-up and<unk> rict return precautions
Sinus tachycardia
Regular
Wide-complex tachycardia
AV Node Independent
Junctional tachycardia
Narrow-complex tachycardia
Atrial tachycardia 
Ventricular tachycardia