There are many ethical and legal implications based on the scenario. However, the three main concerns are trust, patient safety, and malpractice. At the micro level, the medical assistant practiced outside her scope of practice, which can result in a malpractice lawsuit. The medical assistant does not have a license to prescribe medications. She gave a prescription without the provider's consent. In addition, the antibiotic can cause greater harm than good. The patient can build a resistance to the antibiotic if he or she does not need the antibiotic. At the meso level, the trust and work dynamic between the provider and medical assistant can change. As a provider, I would not feel comfortable working with a medical assistant who lied and used my name to give a patient a prescription I did not authorize. Lastly, at the macro level, the entire practice could be placed on probation or closed because of the malpractice of the medical assistant.

The changes that I will recommend to prevent further episodes of the problem behavior is only having the provider refill prescriptions, or giving new prescriptions. The pharmacy or pharmacist needs to speak with the provider directly. Also, the prescriptions can be electronically sent and the provider will need a PIN or password to send the prescription.

The medical assistant should be terminated or given a final warning. The medical assistant practiced outside their scope of practice and lied when giving a prescription. It is unacceptable and can create a problem for the patient, the provider, and the practice.

The model that I would use to implement the change is the Plan-Do-Study-Act (PDSA) model. According to the Institute for Health Care Improvement (2022), the Plan-Do-Study-Act (PDSA) model is composed of four steps. Step 1: Plan and establish the objectives necessary to deliver the results. Step 2: Do, or implement new processes to test possible effects. Step 3: Study or measure the new processes and compare the results. Step 4: Act or analyze the difference to determine their cause. 

Using the PDSA model allows you to have a plan, implement the changes, measure the changes, and determine whether the changes were effective or not. Being able to measure the changes and their effects allows you to either stick with the old plan or the new plan, or it highlights necessary changes. 
A barrier to implementing the change process might be the electronic healthcare system used at the practice might not allow you to do e-scripts. However, a factor that facilitates that change process is verifying the prescriptions over the phone directly with the provider.