Final answer:
The subsequent dose of verapamil after an initial dose for a patient with symptomatic atrial fibrillation can be 10 mg, administered 15-30 minutes later after monitoring the patient's response to the initial dose.
Step-by-step explanation:
Medical command has ordered verapamil to a patient in symptomatic atrial fibrillation. The subsequent dose of verapamil depends on initial response and healthcare provider protocols. For intravenous administration, an initial dose is typically 5-10 mg given over 2-3 minutes to slow the ventricular rate and alleviate symptoms. If the initial dose is well tolerated and the desired effect is not achieved, a second dose of 10 mg may be administered 15-30 minutes later. It's crucial that this procedure is carried out under close medical supervision with constant monitoring of blood pressure and heart rate, as rapid administration of verapamil can lead to hypotension and bradycardia.