You are the nurse taking care of a patient with asthma. The patient reports using his albuterol inhaler about once a month for wheezing and shortness of breath. Albuterol functions by which of the following mechanisms of action?

You are a nurse at a gastroenterology practice and your patient is being started on ranitidine for gastroesophageal reflux disease (GERD). Which of the following describes the mechanism of action of ranitidine?

You are taking care of a patient undergoing chemotherapy for breast cancer and she complains of nausea. Her physician prescribes her ondansetron for nausea relief. What is the mechanism of action of ondansetron?

You start a patient in the intensive care unit on a drip of phenylephrine, as the patient is persistently hypotensive. You think that this will raise the patient's blood pressure because phenylephrine's primary mechanism of action is which of the following?