What is the first drug of choice for a patient in wide QRS complex tachycardia?

In cases of wide QRS complex tachycardia, the first drug of choice is Amiodarone. This medication is a class III antiarrhythmic agent that is effective in stabilizing the myocardial membrane and has properties that prolong the action potential. This is particularly useful in treating various types of tachyarrhythmias, including ventricular tachycardia, making it well-suited for wide QRS complex situations.

Amiodarone is commonly used in emergency settings due to its efficacy and the broad spectrum of arrhythmias it can treat, offering both rhythm control and rate control. Its ability to slow conduction and alter the myocardial cells' refractory period helps restore normal sinus rhythm in patients experiencing wide complex tachycardia.

Other agents listed, such as Verapamil and Adenosine, primarily target narrow QRS tachycardias, particularly those associated with reentrant pathways in the atria or AV nodal reentrant tachycardia. Ibutilide, while used for wide QRS tachycardia, is often reserved for specific cases and not typically the first drug to be administered due to higher risks of complications and is not as commonly employed as Amiodarone in acute settings.